Prime Minister Gordon Brown said on Friday that the new measures being introduced by his government would help to save people from losing their homes, as repossession has surged to a 12-year high in the UK.

"We're going to do everything we can to stop repossessions," he said on a visit to his Fife constituency, on the same day that new figures from the Council of Mortgage Lenders showed the number of UK homes repossessed last year jumped by 54 per cent to 40,000.

The prime minister said, "We're signing agreements with the building societies and the banks that there is a moratorium on repossessions for people with these banks and building societies. And we're introducing measures in the next few days that will be able to underpin people trying to get their mortgage terms of repayment changed."

His comment came as it was announced that a government scheme to help people who lose some or all of their income stay in their home will not be available until April.

The Homeowners Mortgage Support Scheme was announced in December last year, but the government only published final details of the scheme's design on Friday. Under the scheme, homeowners who lose some or all of their income will be able to defer up to 70 per cent of their mortgage interest payments for up to two years.

The scheme was delayed due to protracted negotiations with lenders over how it will work. It remains under sharp criticism, as there is confusion over the details. The Tories are accusing Brown of raising false hopes.

Shadow housing minister Grant Shapps said the scheme, which was meant to help people facing a sudden drop in income to defer mortgage payments, was announced with "flourish", but the details had not been fully worked out and lenders had not signed up to it to the extent Brown had claimed.

He told BBC Radio that it was "completely wrong for the government to announce a scheme where the details haven't been worked out, and where months later, people's expectations will have been dashed."

Liberal Democrat leader Nick Clegg said, "The much-publicised Homeowner Mortgage Support Scheme announced last year has not yet helped a single family in trouble. The prime minister's wasteful complacency means that millions of extra families could be added to already full social housing lists."

Sue Anderson, of the Council of Mortgage Lenders, said the apparent delay in implementing the policy had "caused consumers some confusion and some sense of not knowing where to turn in the meantime".

But she added, "When there is a gap between an announced policy measure and its implementation, inevitably people wonder what's happening and try to find out about that."

In December, Brown had said eight major mortgage lenders had signed up to the plan in principle. But the government is still locked in talks with lenders over how the scheme, which is meant to cover mortgages worth up to £400,000, will work.

The idea is that lender and homeowner will agree on the proportion of payment to be deferred up to 100 per cent, but the government is reported to have clashed with lenders over the extent to which it will underwrite it.

Asked to explain the apparent delay, Chancellor Alistair Darling told a TV interviewer that people would be able to benefit from the scheme "fairly soon".