Gordon Brown is to ask the unions to accept a reduction in their own power within the Labour machine at his first party conference as leader in the autumn.

As David Cameron told Mr Brown that he would welcome an early election, the Labour leader let it be known that he was planning moves to end the confrontational atmosphere at the conference, where the unions and party delegates are sometimes pitted against the leadership. He wants the system under which emergency issues are debated as “contemporary resolutions” to be scrapped and replaced by special debates without a vote.

Mr Brown believes that the moment the debates are organised around a resolution the leadership has to take a line, which sometimes ends in acrimony and defeats. Instead he will suggest “deliberative” debates with the issue then being sent to the party’s policy processes for full discussion.

In a further curb he has proposed that the party’s 200,000 members – rather than the unions – have the final say on Labour’s policy programme through a one-member, one-vote system. A senior aide to the Chancellor said yesterday that the changes were not equivalent to Mr Blair’s move to scrap Clause Four, but admitted that they would be controversial within the party.

Meanwhile Mr Cameron insisted that Mr Brown had no mandate to become Prime Minister tomorrow and urged him to go to the country immediately. After Mr Brown’s coronation speech on Sunday, which put his own party on the alert for a poll, Mr Cameron said that he would be ready for an immediate election.

“If Gordon Brown is serious about wanting to listen to the people of this country then he should call a general election right now,” Mr Cameron said. “Tony Blair said that he would serve a full term but hasn’t. Gordon Brown has no mandate to be Prime Minister and he cannot be the change the country needs. People want real change and the next general election cannot come soon enough.”

The Times has learnt that the Labour Party is telling MPs in safe seats to ensure that they are reselected by their local parties before the end of July, fuelling rumours around Westminster of an early election.

A party source said: “The party has been ringing for two or three weeks and telling people that there is an ‘absolute deadline’ at the end of July for MPs to get their nominations reconfirmed. A third of the party – those MPs in safe seats who are staying on – could do this procedure at any time, but are being told they must do it right away.”

Although this is a matter for constituency parties, the Labour Party machine has appeared so keen to speed up that they are approaching MPs’ parliamentary offices if they cannot reach the constituency secretary. Mr Brown was working on his plans yesterday to change the machinery of government and drawing up his first administration.

Election speculation may be dampened by the latest poll. A Communicate Research survey for The Independent gave the Conservatives a five-point lead over Labour, a one-point increase over last month.

Times Recommends

• Fern Britton: 'I still can't see that I was wrong'
• Extreme cooking
• Easy French: Tarte Tatin