Britain may lose its top credit rating unless borrowing is cut faster, that is the conclusion of George Osborne after spending the majority of last night digesting Alistair Darling’s Pre-Budget Report.

In an interview with Reuters Mr Osborne spoke for the first time of his fears that Britain could be stripped of its AAA credit rating.

“The bulk of dealing with the deficit has to come from spending restraint,” Osborne said. “Unfortunately, the measures announced yesterday don’t start tackling the deficit until 2014/15 and that is far too late.”

“The thing I am aiming for is making sure that Britain keeps its credit rating.”

Ratings agencies have warned that Britain’s triple-A credit rating, which enables the government to borrow more cheaply than less credit-worthy nations, could be at risk unless the government lays out a credible plan to cut the deficit. Both Standard & Poor’s and Moody’s have said that the countries long-term credit worthiness is at risk if meaningful measures are not implemented to get debt under control.

The Shadow Chancellor has already said that he will deliver an emergency budget within 50 day’s if the Conservatives are victorious next year, and argue that hacking back debt will safeguard confidence and keep interest rates low, enabling a sustainable recovery to take root.

“We’ve got to keep interest rates as low as possible for as long possible,” Osborne said.

The Conservative leadership believes the Bank of England would do what is necessary to drive growth forward, allowing the party to get painful cuts in spending out of the way quickly.

Interview on the Today Programme this morning, Mr osborne accused the Chancellor of using the PBR for electioneering purposes, and highlight the fact that the national insurance increase will reduce the NHS budget by £446 million because it is the countries biggest employer.

“That national insurance increase will lead to a real cut in health spending.”

He went on to stress the need to deal with the deficit and the importance of being upfront about it.

“It’s got to be honest, we’ve got to stop having a pre-election con. You’ve got to be honest with people that there are tough choices coming,” he added.