MPs are backing a campaign launched by business leaders who want the Ordnance Survey to name the Black Country on its maps.

But the MPs have also called on the Commons authorities to recognise the Black Country as a specific region. MPs who talk about the region in the Commons find that their words are written as "the black country" - without capital letters - when Hansard is published the next day.

This is because there is officially no such region.

But MPs say they have had enough, and have demanded Commons staff change their policy.

They have sponsored an official Commons motion pointing out that the Black Country is home to 1.2 million people.

The campaign is led by Stourbridge MP Lynda Waltho (Lab) and backed by Ian Austin (Lab Dudley North), John Spellar (Lab Warley), Janet Dean (Lab Burton), David Winnick (Lab Walsall North) and Adrian Bailey (Lab West Bromwich West).

Last night they received a boost when the Ordnance Survey agreed to name the Black Country on its maps - if local councils agreed to the change.

Map number 139 is currently called Birmingham and Wolverhampton, but the Ordnance Survey said it would change the name to Birmingham and the Black Country if local councils asked it to.

But Ms Waltho admitted the MPs had made no progress solving the biggest challenge - deciding where the Black Country starts and ends.

She said: "The easiest thing is to use the administrative boundaries of Wolverhampton, Walsall, Sandwell and Dudley councils.

"But historically, the Black Country also covered the whole of the Staffordshire coalfields."

There was no fixed definition of the Black Country, she said. "Half of my constituents think of themselves as Black Country and the other half consider themselves to be in Worcestershire.

"In Smethwick, where my husband is from, some people call it the Black Country and some say it is part of Birmingham.

"So this is one of the obstacles we face." However, Ms Waltho said she had doubts about attempts to create other identities.

A number of councils, encouraged by the Government, have formed a body called Birmingham, Coventry and the Black Country City Region.

But Ms Waltho said: "This includes three important cities, Wolverhampton, Coventry and Birmingham, which each have distinct identities. I'm not convinced by that.

"And one thing my constituents really don't want is to be part of Greater Birmingham or anything like it."

Black Country Chamber of Commerce launched the campaign to put the Black Country on the map last year, following the death of businessman Don Richardson.

The Chamber said Mr Richardson, who helped build the Merry Hill Shopping Centre, had supported the region's economy when it was at its lowest point.

Black Country identity grew when the region rallied round the campaign for £50 million from the lottery for the "Black Country as Urban Park" regeneration project.

Although the bid was unsuccessful, it saw local councils in the area putting aside old rivalries and working closely together.

A spokesman for the Ordnance Survey said: "We would be happy to name the Black Country on the map, if a request was made by the councils in the area."