The Treasury today appointed former HBOS chief executive Sir James Crosby to head an emergency review of the mortgage market.

His brief is to stop mortgage offers from drying up through measures to boost lending between institutions which have been battered by the credit crunch.

Sir James, who led Halifax owner HBOS from its creation in 2001 to 2006, will assemble a team of industry experts plus officials from the Bank of England and the Financial Services Authority to report to Chancellor Alistair Darling by the summer.

He was given an immediate boost today as HSBC launched an audacious mortgage offer to homeowners coming off fixed deals with other lenders. It is feared that when such deals expire millions of borrowers will not be able to get a new mortgage and could lose their house.

HSBC is targeting customers who come off cheap rate fixed deals this year by promising to match the rate for up to two years and a fee.

The appointment of Sir James comes as other banks and building societies withdraw mortgage offers as the cost of raising funds on the money markets increases.

In a separate move, Treasury Minister Yvette Cooper and Housing Minister Caroline Flint will meet lenders next week to try to forestall a possible wave of repossessions.