Bradford & Bingley last night struck a deal to avoid taking an additional £1bn in mortgages on to its balance sheet after the beleaguered lender renegotiated an agreement with GMAC-RFC, the UK arm of the US financial group.

The agreement eases the pressure on B&B, which is already under pressure from rising arrears on its existing mortgage book and on Tuesday had its credit ratings cut by two of the largest ratings agencies.