Black Country council leaders say no to Metro Mayor in 'Greater Birmingham' plan

And they say the joint body, which will oversee regeneration, transport and skills, should be called 'West Midlands Combined Authority' - ruling out completely any suggestion of a Greater Birmingham.

Councillor Darren Cooper, leader of Sandwell Council, has written on behalf of the Black Country to his equivalents in Birmingham, Coventry and Solihull to set out the 'red lines' for working together.

Wolverhampton, Sandwell, Dudley, Walsall and Birmingham councils have already agreed to create a joint authority but the door was left open to Coventry and Solihull.

But there are concerns that if the name Greater Birmingham is used it will give the impression that it is the second city that is in charge, rather than an equal partnership.

And Chancellor George Osborne continues to float the idea of a West Midlands regional mayor, despite Birmingham having already voted in a referendum to not have one.

The combined authority would allow the councils to work together on projects that benefit the whole of the West Midlands and avoid them having to compete with each other for ever-shrinking pots of government funding.

In the letter Councillor Cooper says: "With regard to the notion of a Metro Mayor, the Black Country Councils would like to use the following wording in our communications:

'A Metro or regional Mayor is not part of the solution for the governance structure of the West Midlands and will not be a part of any agreements to create a combined authority.'

"Secondly, with regard to the name of the combined authority we have to think about what will be acceptable to the individual councils and the residents of the localities.

"The argument that the combined authority will be the vehicle for international business to negotiate with, is in our view as the Black Country, not an appropriate argument as the combined authority will not be operating in this space.

"Therefore Black Country councils believe that the name should be 'West Midlands Combined Authority'.

"We would urge colleagues to support this so that we can give clear direction to officers in regard to the name and mayor issues. This will then allow officers to focus on the economic analysis and other work streams already approved by leaders."

The combined authority would not have any new councillors elected to it.

UKIP has campaigned against the combined authority.

West Midlands MEP James Carver said: "This whole idea is a Labour Party stitch as it is the Labour-run authorities in Walsall, Dudley, Wolverhampton and Birmingham who want to sign away our local democracies to create a combined authority."