"Terribly," says Boris to his cheery director of external affairs, Guto Harri, who has popped in to check how things are going, having been despatched earlier with a breezy, "I'm all right, Guto, don't worry, matey."
Harri returns to find Boris rubbing at the side of his blond mop, looking slightly deranged. "Oh God. Why did I agree to do this interview? I tell you why. Out of sheer vanity."
Boris, downsized after a month of working out with Baby Spice's personal trainer - though still reassuringly dishevelled despite the jacket and tie - is regretting his decision to be interviewed by me over lunch at City Hall, for a magazine politically more in tune with, and which was even once guest-edited by, his rival Ken Livingstone.
Although Boris, according to a poll, is the person with whom most Londoners would like to have breakfast, I've just had mine with Ken, at a café in Hampstead. This has flustered Boris. "That's a different concept -" He shoots Harri a panicky, accusing look. Harri soothes, "It's not a joint piece . . ."
“Did you like him?"
“Yes," I reply.
“Oh God," he moans.
Having worked as a journalist for most of his adult life, "endlessly attacking people who would try to take tough decisions and make the world better", he is painfully aware of what will make headlines and what might get him into trouble. His years as a hack, he says, left him with a sense of "self-dislike", which is what propelled him into politics.
“In the end it wasn't satisfying because I was being very cruel sometimes, just sort of sitting there lobbing rocks over people's walls and causing a great deal of dismay without actually having to put myself in the firing line. I thought it was fundamentally unfair."
I wonder if there's a message here for me, should I be considering lobbing a rock his way. It has been said that Boris is brilliantly manipulative, that the famed gaffes and the shambolic façade are deliberate, and that even the humour and bumbling are just artful devices to disguise a ruthless ambition. "Absolute nonsense," he says when I put this to him, "and you are presenting two very unattractive alternatives."
So, if he's neither ruthless nor a buffoon how does he get away with it all? Why is Boris so bafflingly bulletproof? Does the public not care about your scandals? He pauses. He strokes the side of his head.
He looks directly at me, taken aback, he looks away and then at me again, wounded, let down, wronged. I imagine this must be the stunt he pulls at home when he's in the doghouse with his wife.
Finally he says with affected weariness, "Well, you know, I think I am no judge of that. But on all that kind of thing, Jemima, I am really going to take the Fifth." Fine, but surely he has a view on the Leveson inquiry debate about where one should draw the line between privacy and the public interest?
In the past Boris has argued that he had a right to lie to the tabloid press about his private life and that it had no bearing on his fitness for political office. His wife, Marina, is a lawyer. She is eminent in many fields, including privacy, and lodged a successful plea to the Press Complaints Commission against a newspaper that published photos of their children on holiday in Turkey.
Today he is not so forthcoming. "Well, you know, I am sure Leveson will produce a very good answer to that," he says. Oh, come on, all I'm asking for is an opinion on whether the public is entitled to know what politicians get up to in their personal lives. "Um, er. Now I can see why it was such a bad idea to do this interview." Well? "No, of course not," he replies, exasperated. Then, bafflingly, he announces: "Who was the first politician to call for a truth and reconciliation process between politicians and the media? I am the father of the Leveson inquiry - I claim paternity for the whole Leveson inquiry." The word "paternity" hangs in the air.
Boris must be the only politician who has the largest section of his Wikipedia profile dedicated to "controversies". Sacked from the Times for making up a quotation and then in trouble at the Financial Times for plagiarism, he went on to become editor of the Spectator. Later, as a politician, he was sacked by Michael Howard from the Conservative shadow cabinet for lying about having an affair with the journalist Petronella Wyatt. Now, as Mayor of London, he holds arguably the most important job in British politics after the Prime Minister and presides over a £14bn administration covering everything from race and the environment to the economy and transport.
It seems as if every glitch propels Bounce-Back Boris on to greater glory. Recently he is rumoured to have fathered a love child with the art adviser Helen Macintyre. He refuses to talk about family, "but it's a matter of public record that he has four children", Harri informs me later by email (and those are all with Marina - Lara Lettice, Milo Arthur, Cassia Peaches and Theodore Apollo). Ken had cattily remarked over breakfast, when I posed the same question to him, "We [Boris and I] both have five . . . I can admit all mine." It helps Boris's case that Ken has an equally mysterious private life.
I press on with mistakes and his Teflon quality as his eyes dart wildly round the room for an absent Harri. He must know that he gets away with things that most politicians don't.
“Yes, well, until today, I was doing so well," he says. "It was all going swimmingly until I made the fatal mistake."
Flattering the interviewer is another effective evasion tactic - as is digression, of the "I believe I knew your father" variety. "I interviewed him once," he tells me, apropos nothing, "and he said to me, 'I can't continue with this conversation. This interview is now at an end.' We had a furious disagreement about Chinese underpants . . ."
Back to the point: he is lobbying for new legislation on alcohol-related crime in London with a campaign that launched on 8 February. Under the plan, those who commit offences when drunk would be sent to rehab instead of jail.
“Look, alcohol-related violence is a major problem in London, domestic violence in particular. It is one of the few indicators that's been going in the wrong direction. We have done a lot to try to combat it and we have set up a lot of rape crisis centres, another three around the city. But we have got a problem in society generally with alcohol and . . . compared to my sodding, fucking private life, it is far more important!"
It's an interesting idea that will no doubt elicit outraged Daily Mail editorials about the city authorities being "soft on binge drinkers". The Tory high command aren't convinced, but the government is putting up £400,000 for a trial programme this summer.
Boris says he "has always been a libertarian". And when I suggest that his wife's left-leaning ideas (it is said that she first voted Conservative when he stood in Henley in 2001) have softened Boris and fostered in him more of a social conscience, he insists that he was never a reactionary Tory.
On foreign policy, he has always taken the typical Tory line - empire loyalist, ardent supporter of George W Bush during his first term, which he now regrets, blind defender of Israel and advocate of war in Iraq, which he also came to regret. Reacting to accusations of inconsistency, he once countered, "If the climate can change, I don't see why my mind can't!" He is "very much opposed" to war with Iran but, as he says, foreign policy "is not my job". Probably just as well.
“My kind of Toryism," he continues, "is about allowing people to get on and do what they are capable of doing, liberating talent and allowing people to prosper and flourish. What I find maddening about the left and socialists generally is that they are all about trying to restrain people and keep them in their boxes.
“Conservative politics, properly done, is a massive liberating force. The wealth gap in this country hugely opened up under Labour and social mobility froze in the last 20 years. It was during that epoch of Blair and Livingstone and the whole boom in credit that things started to go wrong for this country, and what they forgot about was what was really happening to the bottom 20 per cent.
“If you look at where we are now as a society, we are endlessly focused on the very narrow, newspaper-driven agenda of rage against anybody who creates wealth, and that sort of hatred of bankers and bonuses - which I perfectly understand emotionally - is just [aimed at] the wrong target. What you need to do is focus on what these people could be doing to help those at the bottom."
It's an impassioned outpouring, just as I was about to ask him what he deeply cares about. The Daily Mail sketchwriter Quentin Letts has said that the problem with Boris is that he is not angry enough - "you've got to be angry: you've got to feel things as an MP, but there is no soul, no church in him. No belief." Ken Livingstone has accused him of lacking ideology.
“I'll tell you what makes me angry - lefty crap," he thunders in response. Like? "Well, like spending £20,000 on a dinner at the Dorchester for Sinn Fein!" Take that, Ken.
The Ken-Boris contest used to boil down to competence v charisma, policy v personality. These days, with incumbency records to compare, the area that Boris still falls down on is, as his adviser Harri concedes, "feeling the people's pain". Polls show that Boris is seen as being out of touch with ordinary people struggling in a recession, which is why his remark about his fee for his column at the Telegraph being "chicken feed" - at £250,000 it is roughly ten times the current average yearly wage - was very ill-judged.
Again when I bring it up he gives me that dismayed look, as if somehow I am betraying a code of honour. "Yes," he says resignedly, it was a "very stupid" thing to say. The truth is that likeability, in any case, seems to be more important to the voter than the common touch. Boris has by far the highest approval rating of any Tory.
“I understand why people say that [that I am out of touch] but I think they are wrong," he says. "If you look at our administration and the way we have kept costs down, the way we haven't wasted money, we have cut bonuses across the board, we have had a series of pay freezes.
“Look at the difference between people that are being attacked in the public sector at the moment for their bonuses - but not at TfL, because we have frozen those. I haven't had a pay increase, far from it, nor has anyone else, and we have been absolutely scrupulous with public money. There is a distinction to be drawn between the way we spend money and the way the previous administration has spent money."
Ken, although perhaps more parsimonious about his personal needs, was not only profligate, Boris argues, and "contemptuous of taxpayers' money", but even argued for less regulation of the banks.
“I am the guy who has concentrated on spending their [the taxpayers'] money where it really counts for Londoners," he says. "I haven't been so arrogant as to squander it on things that would bring no benefit to the people of this city at all, like flying off to bloody Havana and shacking up with Fidel Castro for a while. What is the point of that; how does that help Londoners? Show me the jobs that brought to London. The difference between him and me is that he used huge sums of taxpayers' money for his own self-publicity - he spent £12m on a freesheet he used to shove through people's letter boxes, proclaiming his achievements."
There is an unfortunate piece in a recent issue of Private Eye that he has not yet seen, but which criticises his own pet projects. Although "Boris Island" - an airport in the Thames Estuary - has apparently won the approval of the Prime Minister, the ArcelorMittal Orbit, the red steel helter-skelter sculpture in east London, is apparently "not the free gift to the metropolis that many believe". "The Orbit," the mayor states grandly, "is an important addition to the Olympic Park." Or the Johnson, as Ken has nicknamed it.
Boris sighs. "The issue with the Olympic Park is how do you get people to go there in 2013, 14, 15, 16 and how do you justify £9.3bn of investment in east London?" He uses my name, like a weary parent - not cross, but disappointed. "Jemima, we needed to create something that would serve as a focus for the Park, and I think that the Orbit is tremendous. One of the best things about it is it has a great deal of private support in the form of a donation from ArcelorMittal."
It will still cost the taxpayer more than £3m, won't it? And profits will revert to its eponymous benefactor. "Whatever the figures are, yes, that's right," he replies a little too dismissively. Boris needs to be more specific about his figures if he plans to debate Ken again on television. Ken is as beady with numbers as Boris is linguistically gifted.
He also defends the £60m, kilometre-long pontoon due to grace the Thames this summer. River Park has been delayed, he says, because of "planning issues" and not, as has been claimed, because of dodgy financing by a group called Venus which had not been vetted thoroughly.
Again the faux-weary tone. "To the best of my knowledge the business they have conducted with the various contractors they have taken on has been done properly and I have no reason to doubt they're bona fide . . ."
Equally, the cable car across the Thames from the Greenwich peninsula to the Royal Docks, which will cost the taxpayer at least £26m, has "a great business case, whenever it is delivered". The rumour is that it won't be ready in time for the Olympics. "At the moment it is going very well," he says unconvincingly.
He slumps. "Look, you can't just beat me up in the bits where . . ." He trails off. "I know what you'll write: 'At this point he went silent . . .'"
One of Boris's advantages over Ken might be that he knows every journalistic trick. He is extraordinarily conscious of how he will appear in print and of how his comments will be reported. Unlike Ken, he points out, he has no need for a Matthew Freud PR push at public expense. He is constantly vigilant, on the lookout for the tripwire. "That might have been my cagey look," he says, when I question his expression, "my mind scooting very rapidly forward, thinking: 'Where is she going with this one?'"
If he's so canny, what does he think the headline for this interview will be? "The headline is obviously 'The man to win - why I back Boris, by Jemima'. That is the headline."
His old headmaster at Eton has said that Boris was by far his most interesting pupil. Does he think David Cameron, who was at Eton at the same time, is irked by his charisma? "I yield to no one in my admiration for Dave and everything he is doing." It's a non sequitur, but under no circumstances will he risk a "Boris attacks Dave" headline. My favourite moment from his surreal interview with Jeremy Paxman on Newsnight last October was when Boris was asked, "Do you feel intellectually inferior to Dave?" To which he retorted incredulously: "Inferior?"
So, is he cleverer than the Prime Minister?
He says no, but means yes. "It's a ridiculous question," he tells me. "Different people are good at different things."
In praise of Murdoch
Legacy projects aside, I want to know what he thinks is his greatest achievement as mayor.
“I think it is the big things that I am proud of: reducing the cost of London government and focusing the money where it matters. From that flows everything else - delivering the best car scheme in the world, cutting people's council tax, giving them a 24-hour Freedom Pass.
“We've greatly reduced crime, and it hasn't been easy because it has been a tough period to be mayor. We have still got crime down by 10 per cent; the murder rate is down by about 25 per cent, and you can't fudge that - so, great credit to the Met and to law enforcement generally. Bus crime is massively down, by 30 per cent; people were getting really hassled on the Tube. We have got a 40 per cent reduction in delays in my four years compared to the previous four years. I am proud of this."
“Yes, you ought to put all this in," says Guto Harri, who has reappeared, helpfully.
What of the Metropolitan Police's failure on his watch to investigate phone-hacking properly? Boris, who was friends with the News International chairman, James Murdoch, and with Rebekah Brooks, initially called the allegations "a load of codswallop cooked up by the Labour Party". Later he said he had "misunderstood the severity of the allegations". News International, it should be noted, had discussed sponsoring a mayoral academy and backed many of Boris's policies in its newspapers.
He now concedes that News International did have too much influence over our politicians and police. But, in defence of Cameron, he says: "Well . . . I think it was important to make the case to News International about what the Tories were doing and at least he didn't have slumber parties with them . . ." That's a swipe at Sarah Brown, who did.
Boris was especially full of praise for Murdoch Sr, saying at one point, "What Rupert Murdoch has done for British journalism over the last 30, 40 years is actually very considerable." Does he feel the same way now that it has emerged that some officers at the Met, over which he presided, appear to have been on Murdoch's payroll?
“Certainly it now looks as though that fellow with the beard whose name escapes me . . . What's his name? Wolfman. Write down 'Wolfman' [he means Neil Wallis, the former deputy editor of News of the World]. The problem with Wolfman was that he obviously had become part of the furniture at the Met when he was doing consultancy for News International at the same time. That clearly wasn't OK, and that is my objection."
The condemnation is not exactly damning.
For such a notorious maverick, Boris seems maddeningly cautious and unforthcoming, which makes him less fun than I had anticipated. I sense that he is caught between wanting to show off and having to rein himself in, constantly fighting an inner battle between controversial columnist/TV personality and Conservative politician. At the moment, the politician is winning.
This is Boris Johnson's dilemma. He knows that what makes him popular is also what stops other people from taking him seriously as a politician. There's one moment when he starts off, conspiratorially: "I have just heard the most amazing story about Ken's general protoplasmic -" but he stops himself mid-sentence and trails off. "Anyway, I don't want to talk about that." He can't be persuaded to continue. He looks at me rather pleadingly, apologetic, as if he knows he's giving me a watered-down version of Box-Office Boris. "This is not the moment in the electoral cycle." His alphabetical print tie is now disarmingly askew.
Losing my ambition
We still haven't eaten, and now Boris is late for his next appointment. He suggests that we grab a takeaway from the City Hall canteen on the ground floor. We get fish and chips in a cardboard box, which he pays for at the till with a crumpled note, and we wolf it down in seconds back in his office, like students. Aides hover and he's ready to go before I have finished eating.
The question everyone wants answered is whether he harbours ambitions to be prime minister. It elicits a well-rehearsed response: “I think that my chances of being prime minister are vanishing . . ." I've heard variations of this before: "I have as much chance of becoming prime minister as of being decapitated by a Frisbee or of finding Elvis . . ."
“Honestly, Jemima," he says after a pause, dispensing with theatrics, "the only job I want is to be Mayor of London for the next four years." After another pause he says, equally seriously: "I work harder now than I have worked since I was 16." He even offers to show me his alarm clock to prove it. And I'm pretty sure he's not propositioning me.