If the full costs of nationalising banks such as the Royal Bank of Scotland are included, then the debt figure hits £2.3 trillion.
The Treasury blamed Labour's "unsustainable level of spending".
The IMF warned the eurozone crisis was pushing the world economy "deeply into the danger zone".
It also suggested the emerging markets in central Europe and Asia could be hit by a knock-on effect.
The IMF predicted the UK would grow at just 0.6% this year, down from previous
forecasts of 1.6%, and then grow 2% in 2013, down from 2.4%.
Today, the official GDP figures for the final quarter of 2011 are expected to show the British economy continuing to stagnate. The Office for Budget Responsibility predicted that while Q4 of last year would be -0.1%, Britain would avoid another recession because Q1 of this year would be positive, albeit only just 0.1%.
The IMF warned global output would expand at 3.25% this year, a revision from 4%. The eurozone would suffer a "mild recession," it said.
Elsewhere, the Office for National Statistics said the public sector net debt had passed the £1 trillion barrier, or 64% of GDP, as the Coalition borrowed nearly £14 billion in December.
Meanwhile, Sir Mick Jagger last night pulled out of a pro-Britain event involving Prime Minister David Cameron at the world economic forum at Davos, Switzerland, saying he was being used as a "political football".