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By Sumeet Desai

LONDON, Nov 5 (Reuters) - The Bank of England expanded its asset-purchase programme by 25 billion pounds on Thursday, halving the pace at which it buys bonds and suggesting the scheme to revive Britain's recession-hit economy may be coming to an end.

Sterling shot up around a cent against the dollar and government bonds tumbled as many investors had expected a bigger expansion of the eight-month-old programme to buy assets, mostly UK government bonds, with newly-created money -- otherwise known as quantitative easing (QE).

"We suspect that this will be the final extension to the QE programme unless the economy suffers a major relapse in 2010," said Howard Archer, economist at IHS Global Insight.

The BoE, which also left interest rates unchanged at a record low of 0.5 percent as expected, said the bond purchases would take three months to complete as it has halved the pace at which the buying would be conducted.

Up to now the BOE undertook three gilt purchases a week but will now do two in one week and one in the next.

The QE programme started in March when the BoE first cut interest rates to 0.5 percent with a promise to buy 75 billion pounds of assets over three months. The scheme was then expanded by 50 billion pounds each in May and August.

Economists said any interest rate rises were still a long way off. The U.S. Federal Reserve this week also signalled rates would be kept ultra-low for some time to come and the European Central Bank on Thursday left borrowing costs at a record low of 1 percent.