With David Cameron still away in the US, it's Nick Clegg who will man the dispatch box at PMQs today, and we can expect the Tories to take full advantage of the occasion to remind Clegg of the days when he supported an in/out EU referendum.
The Deputy PM now rejects a vote on Britain's membership as against "the national interest" but as the leaflet below (thought to date from 2008 ) shows, he was previously calling for a "real referendum" and denouncing Labour and the Tories for not doing the same. The leaflet declared:
It's been over thirty years since the British people last had a vote on Britain's membership of the European Union.
That's why the Liberal Democrats want a real referendum on Europe. Only a real referendum on Britain's membership of the EU will let the people decide our country's future.
But Labour don't want the people to have their say.
The Conservatives only support a limited referendum on the Lisbon Treaty. Why won't they give the people a say in a real referendum?
In fairness to Clegg, this pledge was specifically tied to the Lisbon Treaty and, while the Lib Dems' 2010 manifesto repeated the promise of a referendum, it suggested that one should be only held "the next time a British government signs up for fundamental change in the relationship between the UK and the EU." Since the UK is currently not negotiating a new treaty, Clegg will argue that the preconditions for a vote have not been met. But in the heat of the Commons, this detail is likely to be lost. Expect Tory MPs to bombard Clegg with questions accusing him of showing "complete disdain " for the British people and of breaking yet another election pledge.
The Lib Dems are clear that they will not waver on the question of a referendum, with one source telling the Telegraph : "We won’t give up any government time to internal Conservative Party politics." But as Clegg knows all too well, there are few things more toxic for his reputation than his image as a man who never keeps his word. And with the Tories already in election campaign mode, no punches will now be pulled for the sake of their coalition partner's feelings.
As I noted at the weekend, Michael Gove used  his interview on The Andrew Marr Show to portray Clegg as a man too weak to support government policy (in this instance on childcare ratios) due to the internal threats to his leadership. Today, he will be assailed as a hypocrite, a liar and a scoundrel. The "Rose Garden moment" now feels a very long way away indeed.