Livingstone could return to Labour Party within weeks

Ken Livingstone could rejoin the Labour Party within weeks under a plan approved by Tony Blair. But Mr Livingstone insisted any such move would not stop him from speaking out on issues such as Iraq.

The Prime Minister is understood to have agreed in principle to explore ways of getting Mr Livingstone on board well before next June's London mayoral election. Ian McCartney, the party chairman, has been asked to look at allowing the national executive committee (NEC) to invite Mr Livingstone to rejoin before the end of the year. The NEC narrowly voted against allowing him to rejoin last year.

The former GLC leader, who was expelled for five years when he decided to stand as an independent in the 2000 mayoral race, may even get the key support of Nicky Gavron, Labour's current official candidate. Ms Gavron believes her support is holding up but many expect her to finish fourth. If she can be given the job of deputy mayor - a position appointed by the Mayor - with a wide remit over policy, she may step aside.

In a further boost to the Mayor, sources close to Gordon Brown, the Chancellor, dismissed speculation that he was actively seeking to block Mr Livingstone's return. Labour MPs who had previously opposed Mr Livingstone's return, including former Parliamentary Labour Party chairman Clive Soley, are also reconsidering.

Mr Soley told The World At One on BBC Radio 4: "Given the way he has moved and the way he's changed, I'm prepared to make that work. It's not easy. There's an element of saying it is not ideal, but maybe on probation or whatever."

Under the plan, Mr Livingstone would not need to make a fresh application to rejoin the party - a detail that itself may be open to legal challenge. Instead, the NEC would formally invite him to rejoin.

Mr Livingstone told BBC London yesterday: "Until it is sources in Number 10, until the tall man with the smile sings, it isn't over. If I'm offered it, I'll take it. I think both the Prime Minister and myself recognise we are not going to change each other. We have learnt to accept each other.

"If I'm the Labour candidate [for Mayor] next summer, it won't mean I'm supporting the war against Iraq and it won't mean he supports everything I say about President Bush. In a grown-up world, you've just got to accept the fact that politicians don't all believe the same thing."

When Mr Livingstone stood as an independent against Labour's Frank Dobson in the 2000 mayoral election, Mr Blair was scathing about his past connection to the "loony left" in the capital. And before the NEC rejected Mr Livingstone's application to rejoin, John Prescott, the Deputy Prime Minister, was equally severe, accusing him of telling "a tissue of lies" about his intention not to run as an independent.

But with Labour facing the humiliating prospect of fourth behind Mr Livingstone, the Liberal Democrats and the Tories, Downing Street has listened to pressure from the capital's MPs. A Livingstone victory for Labour would also give the party a much-needed fillip before a general election.

Many believe the real threat to Mr Livingstone's mayoralty comes not from the Tory candidate, Steve Norris, but from the Liberal Democrat Simon Hughes. Mr Norris said yesterday private polling indicated Mr Livingstone would lose support as an independent.