Exodus of Labour big guns who aim to be mayors or police chiefs

A string of heavyweights aims to copy Boris Johnson by launching careers outside Westminster, including former deputy prime minister Lord Prescott, ex-defence secretary Bob Ainsworth and former Europe minister Gisela Stuart.

The sudden enthusiasm for pastures new among MPs who were only re-elected in 2010 is seen by some as evidence of gloom about Mr Miliband's chances of returning his party to power in the near future. It could mean by-elections in Labour seats this autumn.

Eleven cities are holding referendums in May on creating elected mayors with responsibility for local services. Full elections are due on November 15.

On the same day, the first elections will be held for 40 new local police commissioners, with responsibility for setting crime-fighting priorities. Mr Ainsworth told the Standard he had long hoped to be mayor of his home town, Coventry, where he was once a Jaguar plant shop steward.

"It is something I have wanted to do for years," he said. "I would certainly give up my Westminster seat because mayor is a full-time job and I would dedicate myself wholly to it."

Mr Ainsworth said he felt cities were currently held back by the "fragmented" power of traditional council leaderships, based on committees of councillors.

Other cities that want to create mayors are Birmingham, Bristol, Bradford, Leeds, Liverpool, Manchester, Newcastle, Nottingham, Sheffield and Wakefield. Leicester chose former MP Sir Peter Soulsby as its first elected mayor last year.

Ms Stuart is tipped to stand in Birmingham. Shadow work and pensions secretary Liam Byrne, a Birmingham MP, is also said by Labour colleagues to be considering running.

Lord Prescott has said he is interested in being a police and crime commissioner, probably for the Humberside force, although he has not yet made up his mind. "It's an interesting time for a man like me," he said recently.

"The commissioners are going to be people who have some influence and I can't help but feel the personalities of the individuals will be important."

Former Welsh first minister Alun Michael is bidding to be nominated as the Labour candidate to be police and crime commissioner for South Wales. He recently pledged to give up his Westminster seat if successful.