Alistair Darling, Britain's treasury chancellor, said that the rescue plan would extend the window for its Credit Guarantee Scheme, which underwrites debt for banks that were recapitalised by the government to the end of this year.

Under the latest British plan, lenders would have to identify their riskiest assets, which they could then insure with the government for a fee.

It is extending the Bank of England's Special Liquidity Scheme, which expires this month and allows financial institutions to swap hard-to-trade assets for more liquid ones.

In addition, the package builds on the recommendations of a government-sponsored report that called for guarantees of the mortgage-backed securities market.

Britain's treasury said it would also no longer run down the loan book of Northern Rock, the bank it nationalised last year.