The Staggers 3 April 2012 Boris erupts at Ken "You're a fucking liar," Johnson tells Livingstone after exchange on tax avoidance. Print HTML Boris Johnson and Ken Livingstone's relationship appears to have reached a new level of fractiousness. The Guardian's Hélène Mulholland reports that "Boris went nose to nose with Ken in a small lift and told Ken three times: "You're a fucking liar, you're a fucking liar, you're a fucking liar." The mayor's outburst, since confirmed by Livingstone's team, was prompted by an exchange on tax avoidance during the LBC hustings. Livingstone alleged that Johnson, like him, had set up a company called "Finland Station" to channel his income payments, a claim the mayor flatly denied. Here's the statement Team Johnson has issued: My salary as Mayor is taxed as an employee of the GLA. In the same way as when I was an MP my salary was taxed as an employee. Any other income that I have received from outside endeavours has been received on a self-employed basis, to me as an individual (no company or other structure has been involved). No income earned by me has ever been paid to a "service" company, through which a person or person's freelance earnings can be channelled so that they pay corporation rather than income tax. To suggest otherwise is a complete and utter fabrication. Of course the real point is not about my tax arrangements. It is about the hypocrisy of a man who for years has railed against those who use special arrangements to reduce their tax and who has then been caught – bang to rights – doing the very same thing himself. › Reviews round-up No love lost: Mayor of London Boris Johnson and Ken Livingstone. Photograph: Getty Images. George Eaton is political editor of the New Statesman. From only £1 per week Subscribe More Related articles The Fire Brigades Union reaffiliates to Labour - what does it mean? John Gray on the future of the state on the NS Podcast Could Labour lose the Oldham by-election?