Gordon Brown has insisted the Government would still go ahead with plans to spend its way out of the looming recession, despite a massive rise in public sector debt.
Official figures showed net borrowing hitting a record £37.6 billion between April and September - higher than the whole of the previous year.
The sharp increase left Chancellor Alistair Darling's forecasts of £43 billion of borrowing this year in tatters and led to warnings that debt could balloon to £120 billion in three years.
In the Commons, Tory leader David Cameron warned the country was entering the global economic downturn with "the highest government deficit in the industrialised world".
In exchanges with Mr Brown, he pointed to one economic forecast predicting that total debt this year could hit £64 billion.
"Isn't the £64 billion question this: why, when business and families need more help, has he left the cupboard so bare?" he demanded.
The Prime Minister however insisted the public finances were in good shape and the Government could afford to borrow to finance a major programme of public works - outlined by Mr Darling at the weekend - in a bid to stave off the worst effects of the downturn.
"It is because we cut the national debt over the last few years that we are able to do what is the right thing," he told the House.
He cited figures from the International Monetary Fund which put debt in Britain at 37.6% of national income, compared to 55.5% in France, 56.1% in Germany, 101.3% in Italy, 46.3% in the United States, and 94.3% in Japan.
However more recent figures for September, which include the liabilities of the nationalised Northern Rock, show that debt in the UK has since risen to 43.4%.
