Lloyds TSB and Abbey were last night alone in promising to pass on the one and a half percentage-point cut in base rates to homeowners.

The majority of high street banks and building societies responded to the cut with a scramble to prevent new borrowers from taking advantage of the Bank of England’s decision, hastily withdrawing almost all mortgages deals that are pegged to the base rate.

By last night every major lender had pulled their tracker deals with the exception of HSBC, Britain’s biggest bank, the Cooperative Bank and a handful of small building societies.

Mortgage brokers said the full-scale withdrawal from the tracker market in a single afternoon was unprecedented.

Michael Coogan, of the Council of Mortgage Lenders, the industry body that represents banks and building societies, said: “No lender wants to be the last lender in the market because they will be swamped with customers. Trackers will be available in the future but rates are likely to go up because of the cost of funding in the wholesale market.”

The Bank of England cut the cost of borrowing by one and a half points to 3 per cent in an attempt to shore up the economy and stave off a deep recession. The surprise cut took the base rate to its lowest level in more than half a century.

Mr Brown and Lord Mandelson, the Business Secretary, have pressed mortgage lenders in recent days to pass on reductions in the base rate to homeowners.

Yvette Cooper, Chief Secretary to the Treasury, said yesterday: “The Government has stepped in to make the banking system safe, to support the banks. It is right now that the banks do their bit to support everybody else.”

More than four million homeowners on existing tracker mortgages will benefit immediately from the rate cut because their deals are directly linked to the base rate. A household with a £150,000 capital repayment loan will save almost £120 a month on the cost of their mortgage repayments, and £187.50 a month with an interest-only loan.

About 800,000 homeowners are on their lender’s standard variable rate (SVR), or a discounted deal which is pegged to it. No other lenders have committed to cutting their standard variable rates.

HSBC said that its SVR was under review and that it may not announce whether it is passing on the cut until next week, leaving homeowners in limbo. On Monday, a senior executive at HSBC gave warning that borrowers on its variable rates were unlikely to benefit from the full cut.

Other lenders, including Royal Bank of Scotland and Nationwide, the UK’s biggest building society, have also said their SVRs remain under review and insiders predict that they may not make an announcement until after the weekend. Less than half of lenders passed on last month’s half-point cut in interest rates in full.

Melanie Bien, of the brokers Savills Private Finance, said: “Lenders are really going to struggle to pass on the full cut. No one expected the base rate to be cut this far. It should have a massive effect on the mortgage market. This is a historic, dramatic reduction.”

Lloyds TSB is reducing its SVR to 5 per cent because of a clause in its mortgage contracts promising that its variable rate will never be more than 2 percentage points above base. Halifax, the UK’s biggest lender, recently scrapped a similar clause in its mortgage contracts and says its SVR is still under review.

Mortgage brokers have also given warning that thousands of borrowers may not benefit from future cuts in the base rate because many lenders have a “collar” which stops tracker rates falling below a certain level.

Meanwhile, savers have been urged to snap up top-paying fixed rate bonds fast, as they could be gone in days.

Returns on savings accounts have been at seven-year highs for much of this year, as lenders have become increasingly reliant on consumer deposits to fund their mortgage book. But, after the shock base rate cut, best buy deals of more than 6.5 per cent on savings accounts and 7 per cent on bonds are expected to disappear.

Abbey said that it will cut the top rate on its one and two-year fixed rate savings bonds by one percentage point on Monday. Anyone who applies before the end of Sunday will lock into a rate of 6 per cent, before it drops to 5 per cent on Monday.

Bradford & Bingley, also part of Santander, is pulling its fixed savings bonds on Saturday night, and has yet to decide whether to replace them.

Savers have been urged to keep an eye on their accounts in case banks and building societies use this opportunity to cut rates dramatically. When the base rate was last cut, by half a percentage point in October, some banks and building societies made even bigger reductions.