Gordon Brown is to keep the prospect of an early general election hanging over his party and the Conservatives throughout next week’s Labour conference.

The Prime Minister is expected to make plain tomorrow that he will not use his keynote speech on Monday to announce an election, and that ministers will concentrate through the week on showing they have the vision and programme for Britain’s future.

But after a string of council byelection wins, and polls suggesting that he could win a three-figure majority, Mr Brown has decided to leave open the door to an early poll. A startling byelection victory on Thursday in Worcester, one of the seats the Conservatives would have to win in a general election to form a government, has buoyed Labour strategists, many of whom now hope Mr Brown will take the plunge.

The conference will open tomorrow with a speech by Alistair Darling, the Chancellor, and a debate on Mr Brown’s proposals for changes to the conference structure that will reduce the influence of the unions. He appears to be assured of victory. Mr Brown will speak on Monday.

Polls last night gave Mr Brown another boost. A YouGov survey in The Daily Telegraph showed him with a clear lead.

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