Alistair Darling on Monday offered what appeared to be a quick shot in the arm to the mortgage lending market, promising to implement recommendations made by Sir James Crosby that mortgage-backed securities should be covered by government guarantees.

Sir James’ report, commissioned earlier this year, was finally released on Monday. It concluded that lenders’ inability to obtain capital to lend to homebuyers “was the sort of market failure that might call for government intervention, perhaps even on a significant scale.” Indeed, he suggested, the shortage of funds was so severe that it was now very likely that net new mortgage lending would fall below zero.