Whitehall is to impose an elected mayor on Birmingham without asking residents whether they want one, ministers have confirmed.

Local Government Minister Bob Neill let the cat out of the bag at the Conservative Party Conference in Birmingham, when he confirmed a referendum would be held – but only after a mayor had been created.

Ministers will impose dramatic changes on local government and then ask residents at a later date whether they want to stick with the reforms or go back to the old system.

There has been speculation since May that the coalition Government planned to force big cities to adopt mayors, but this is the first time Ministers have confirmed the plan.

Meriden MP Caroline Spelman, a former Shadow Local Government Secretary, revealed last year that Conservatives wanted to create mayors in Britain’s 12 biggest cities, including Birmingham and Coventry,

She said that referenda would be held in the cities first, to discover whether local residents wanted a mayor or not.

But the detailed programme for government published by the Lib Dem/ Conservative coalition in May, stated: “We will create elected mayors in the 12 largest English cities, subject to confirmatory referendums and full scrutiny by elected councillors.”

It was unclear what “confirmatory” meant, and ministers refused to explain whether the policy had changed.

Local government minister Bob Neill has now confirmed that mayors will be put in place first and a referendum held later, in an interview with the Local Government Chronicle. Asked how confirmatory referendums would work in practice, he said: “[The question will be] we have set up these things, do you want to stick with them?”

And asked if that would mean existing council leaders being made mayors, he replied: “That would seem the easiest way of doing things, yes.”

The policy is likely to spark fury among opponents of a mayor, who include Conservative city council leader Mike Whitby.

The Birmingham Post’s sister paper, the Birmingham Mail, launched a campaign in 2007 calling for a referendum on a directly-elected mayor. Despite gathering 10,000 signatures it fell far short of the 36,000 needed to trigger a ballot under legislation in force at the time. But the campaign also sparked a backlash from councillors fiercely opposed to a mayoral system.

The Government’s stance also appears to fly in the face of Conservative pledges to devolve power to local communities, as it means a major change is taking place in local government without consulting residents.

Local Government Secretary Eric Pickles refused to answer questions about a referendum when quizzed by journalists during the party conference. But in his speech to delegates, he confirmed his enthusiasm for elected mayors.

Mr Pickles said: “I believe elected mayors in cities will be embraced by the public if they have real powers. It’s time for Home Rule for our cities, from Birmingham to Bristol, from Newcastle to Liverpool.

“Just over a hundred years ago, the power of civic pride and mayoral leadership was plain to see right here, in Birmingham. Imagine what could be achieved by a 21st century generation of Joe Chamberlains, championing civic pride and social renewal.”

Mr Neill’s admission was criticised by Liberal Democrat MP John Hemming (Yardley). He said: “It doesn’t sound very sensible to me. And it raises the possibility of somebody standing for the post of mayor on a platform of abolishing the post.”

Labour MP Gisela Stuart (Lab Edgbaston) said: “I think a directly elected mayor will be a good thing for Birmingham but it is getting off to a bad start if the Government can’t be up-front about its intentions.”

So far, only one candidate for the post of Mayor of Birmingham has officially come forward – former Labour Erdington MP Sion Simon.

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