Ken Livingstone's admission that he would like to return to the Labour Party has brought a mixed response from the capital's Labour MPs.

Backbenchers have questioned how the former MP could be re-admitted into the party and stand as Labour's candidate.

According to reports Tony Blair has agreed in principle that the London mayor should be allowed to return to the fold before his formal ban comes to an end.

But two of London's leading MPs told ePolitix.com that there is a serious question about how he could be allowed to stand as Labour's mayoral candidate.

Party strategists have been considering their options after opinion poll data revealed Labour's official candidate Nicky Gavron could be run into fourth place.

If nothing changes then she will have to fight not only Livingstone but also Steve Norris for the Conservatives and the Liberal Democrat heavy-hitter Simon Hughes.

Former transport minister Glenda Jackson told ePolitix.com that she wanted Livingstone to be brought back into the party.

"I see absolutely no reason why he shouldn't be back in. He's always been a member of the Labour Party spiritually, politically and emotionally," she said.

"He's been an extremely good mayor and supported Labour candidates."

Former Downing Street adviser and Dagenham MP Jon Cruddas repeated his support for "Red Ken".

"I'm a pragmatist. There's a lot of common ground between Ken and the prime minister. The policies of the mayor are consistent with what I think a Labour mayor could do," he said.

"It should not be beyond the collective wit to sort this out."

But both MPs admitted it would be difficult to ease Gavron out.

"Nicky Gavron cannot be sacked: the party elected her. If she wants to stand down that's a different kettle of fish but then do we go through the selection process all over again?" said Jackson.

Cruddas argued that Labour's rules had been flexible when MP Shaun Woodward crossed the floor from the Conservatives.

"We've got to put the past aside. We have to think what is best for the party and think what is the best route for us to take," he said.

"Nicky would be a very good candidate but at the same time I know she worked very closely with the mayor as his deputy."

The renewed speculation came after Livingstone told the BBC that he would accept any opportunity to renew his membership of the Labour Party.

Growing signs of a rapprochement have also led him to say he would like to run as Labour's candidate in next June's mayoral race.

He was thrown out of the Labour Party following his decision to stand as an independent candidate.

In recent weeks Livingstone has worked hard to show that his old battles with Labour's high command are a thing of the past.

He canvassed on behalf of Labour's candidate at the Brent East by-election.

He recently joined the prime minister for a photocall for the launch of the latest stage in the Thames Gateway initiative.

Livingstone claimed he had developed a working relationship with the prime minister.

"Both the prime minister and myself recognise we are not going to change each other; we have learned to accept each other," he said.

"If I am the Labour candidate next summer it doesn't mean I am supporting the war against Iraq, it won't mean he supports everything I say about President Bush."