Bradford will gain a temporary ‘elected mayor’ before residents are given a say on whether they want one permanently.

Bradford Council leader Ian Greenwood will automatically become “shadow mayor” from next summer, even though a promised referendum on the switch will not be held until May 2012.

Coun Greenwood will gain the ability of existing mayors, such as in Stoke and Middlesbrough, to take certain decisions without the backing of Bradford’s ‘cabinet’ of councillors.

The move will be revealed when Communities Secretary Eric Pickles, a former Bradford Council leader, finally publishes his long-delayed Localism Bill today.

Critics of the plan to “rebadge” council leaders as mayors believed they had defeated the idea, but now it has been revived.

Mr Pickles believes awarding the temporary title will help fire Bradfordians’ enthusiasm for voting ‘yes’ in the referendum to follow on whether the district should have an elected mayor, amid fears of an embarrassing defeat.

A Government source admitted: “Shadow mayors will have the same powers, essentially. It’s about conferring the title and status, which will help raise awareness of the mayoral position.”

However, the extra responsibilities to be handed to so-called ‘executive mayors’ will only be transferred after a mayoral election has been staged in May 2013 – if the referendum is won.

But voters will today be no clearer about what those powers will be because ministers have yet to decide.

As a result, the exact powers for mayors will only be set out as the Bill makes its passage through Parliament – rather than when it is published today, as originally promised.

Many insiders believe the plan would have been dumped altogether if it had not been for Prime Minister David Cameron’s passionate personal enthusiasm for mayors.

Last night, Richard Kemp, the Liberal Democrat leader on the Local Government Association (LGA), predicted the referendum would be lost.

Coun Kemp said: “I’m confident that Labour, the Liberal Democrats and Conservatives will campaign together successfully for a ‘No’ vote.

“I believe that will happen in all 12 cities where the referendums will be held.”

Mr Pickles will confirm today that shadow mayors will be created – and referendums held – in Bradford, Birmingham, Leeds, Sheffield, Manchester, Bristol, Liverpool, Wakefield, Coventry, Leicester, Nottingham and Newcastle.

Once the Localism Bill has achieved Royal Assent – probably next summer – a Government order will trigger the switch from council leader, with no power for any of the 12 existing leaders to oppose it.