HBOS, Britain's biggest mortgage lender, is to add an "account" fee of up to £275 to all new mortgages, Times Online has learnt.

While Halifax and Bank of Scotland will charge an extra £245 to set up a new deal from Sunday, their sister subsidiary The Mortgage Business, broker-only lender, will charge £275. The fee will be in addition to arrangement charges already levied by the lender of up to £1,499 on some loans.

The fee hike comes as the Council of Mortgage Lenders (CML) battled on Wednesday to defend the industry against criticism from the government over high charges.

Alistair Darling, the Chancellor, criticised UK mortgage lenders this week for charging flat fees of up to £3,000 and threatened action from the Financial Services Authority (FSA) if lenders did not reduce them. The CML said that constraining the market would be counter-productive.

A spokesman said: "UK mortgage customers continue to benefit from a good choice of mortgages, including hundreds of fee-free deals, even in the current difficult conditions in the mortgage market. Constraining the market to offer products priced in only one way would be detrimental to customer choice.”

However, HBOS's new charge will inflame the row further. It appears to be an attempt to recoup losses made after it dropped its mortgage exit fee last year following a FSA investigation.

The group said the fee is to cover the setting up, routine maintenance and closing down of the mortgage account. It added that the new account fee will be charged upfront but borrowers can add the fee to their mortgage and will not have to pay interest on the charge.

A spokeswoman said: "This new single fee is less than the total of the mortgage exit fee we removed last year plus a number of post completion service fees now also being removed. Many other lenders continue to charge an exit fee."

The average fee on a two-year deal from Halifax has leapt from £374 to £1,174 since June 2006, according to Defaqto, the financial data provider.