Bradford countryside campaigners say green spaces are the “lungs of a town” and branded new development threats to concrete over them “diabolical”.

As part of its strategy to encourage growth, the Government is expected to re-write planning rules and slash red tape. But it is feared the move will make it easier to build on the green belt.

In turn Chancellor George Osborne will encourage councils to allow buildings on such land as long an equivalent space elsewhere is brought into the green belt.

But green campaigners say once the land was gone, it was highly unlikely other land would be reclassified.

Terry Brown, chairman of Greenhill Action Group, said: “We have serious concerns about this and I believe most people will have. We have land designated as green belt and encouraging people to build on it rather than brownfield or derelict space, is wrong. Once it is gone it would never be given back. The Government should not be doing this, green belt should be sacrosanct.”

His fears were echoed by Elizabeth Hellmich, chairman of Heaton Township Association, who said Government must listen to the people who elected them.

She added: “It is diabolical. When green belt was set up many years ago it was said to be the lungs of the town providing clean air for the town. More than ever now this is needed as towns are getting bigger.

“Given how many people are up in arms about building on green belt land the Government should take more notice. Start building on brown field sites and bring back old properties into use.”

Mr Osborne said it was “absolutely ludicrous” that planning applications took so long to be processed.

The planned shake-up is also believed to include curbs on residents’ rights to oppose development in their area.

Bradford Council’s executive member responsible for planning, Councillor Val Slater , said: “This is something that will cause great consternation locally. There are very good local campaigners trying to protect the green belt.

“As a Council we are working hard to identify other alternate sites as we draw up the next stage of our local plan and doing everything we can to protect our highly-valued sites but this may pull the rug from under our feet.”

Shipley MP Philip Davies said: “I am all for simplifying planning procedures for things as such as developments in inner city sites, but I am wholly opposed to anything that makes it easier to build on green belt. That is utterly unacceptable and I think it is already too easy. I spent a lot of my time making sure the Shipley constituency is not concreted over. I will not support anything that makes it easier for this to happen.”