Leading article | The sisterhood | More trouble for Brown | Johnson the favourite | Sketch | Matthew Parris | Alice Thomson | Peter Riddell | Key players: next moves | Has Reid told Brown to go?

Gordon Brown was confronted by an e-mail plot to ditch him and the threat of further ministerial resignations as Labour braced itself for a disastrous showing in today’s European and local elections.

On a day of extraordinary drama it emerged that Labour MPs were being asked to sign a letter tomorrow calling on Mr Brown to go. There are high- level predictions that up to 75 may do so. Hours earlier, Hazel Blears had quit the Cabinet without offering any praise for Mr Brown’s leadership.

The Prime Minister continued with plans to shake up his Government and was preparing to bring Ed Balls into the Treasury despite indications from friends of Alistair Darling, the Chancellor, that he was reluctant to move.

In a sign of the febrile atmosphere, Downing Street was forced to deny claims that Mr Brown had asked John Reid, the former Home Secretary, whether he wanted the job back.

Whips are braced for ministers to unleash fierce attacks on Mr Brown after the polls close tonight. They have been warned that a fifth minister may walk out over the coming days.

The message to Mr Brown, which MPs are being asked by e-mail to sign, reads: “Dear Gordon, over the last 12 years in Government, and before, you have made an enormous contribution to this country and the Labour Party and this is very widely acknowledged.

“However we are writing now because we believe that in the current political situation you can best serve the interests of the Labour Party by stepping down as Party Leader and Prime Minister, so allowing the Party to choose a new Leader to take us into the next General Election.”

The MPs are assured that the names of signatories will not be published unless a target of 50 is reached.

Nick Brown, the Labour Chief Whip, said that he believed that those behind the e-mail were Blairites such as Stephen Byers and Alan Milburn. He said that they had been joined by “eccentric individualists” such as the backbenchers Graham Stringer, Graham Allen and Paul Farrelly. The latter categorically denied the claim on the BBC2 Newsnight programme.

Ms Blears’s resignation, on the eve of the elections, was a godsend to the Opposition. David Cameron said that the fourth ministerial resignation in two days showed that the Government was “collapsing before our eyes”. Nick Clegg, the Liberal Democrat leader, told MPs: “Labour is finished.”

One former minister said that there was huge desire within the party for a change of leadership, but MPs were waiting to see whether a heavyweight challenger would come forward. Alan Johnson remains favourite.

A meeting between Mr Reid and Mr Brown on Tuesday evening led to the BBC claiming that the Prime Minister had asked the former Home Secretary to return to the post. That was vehemently denied by No 10, which said that there had been no job offers. Mr Reid’s office would say only that he was not returning to government.

Ms Blears sported a brooch bearing the words “rocking the boat” as she went in to tell Mr Brown that she was quitting. It was later alleged that her position had become difficult because she had avoided paying capital gains tax on two properties, rather than one. Ms Blears’s friends insisted that she had made plain on her website that the return of capital gains tax related to two properties. They accused whips of trying to smear her.

Ms Blears told Mr Brown on Tuesday that the way in which he had criticised her expenses claims was unacceptable. She spoke to friends and, realising she was about to be sacked, decided to go on her own terms.

In the Commons Mr Brown rejected calls for a general election. He said: “We have got two jobs of work to do. One is to clean up the expenses system. The other is the recession.”

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