Britain’s biggest mortgage lender today defied Gordon Brown’s plea to cut mortgage rates. The Halifax is raising rates on some mortgage offers by 0.5% despite his calling bank chiefs to No10 to urge them to sign up to the Government’s strategy to tackle the global economic turmoil. The Prime Minister was also bluntly warned that a string of building societies could be forced out of the mortgage market by the looming crisis. Mr Brown is said to be prepared to offer banks help to raise funds but wants them to pass on interest rate cuts, do everything they can not to repossess the homes of people struggling to meet their mortgage payments, and to offer loans to first-time buyers. The Bank of England is injecting a further £15bn of liquidity into the markets, taking its total recent support to more than £50bn.