The Alliance Against the Birmingham Northern Relief Road was granted leave to seek a judicial review, and Mr Justice Ognall ordered an urgent hearing of the case.
The campaign group Friends of the Earth, which is supporting the challenge, said that the alliance, representing communities along the 27-mile route of the proposed road, were demanding to see a concession agreement between the Department of Transport and Midland Expressway to check whether it contained cancellation charges.
Legal opinion from solicitors Leigh, Day and Co was that it was unlawful to consider cancellation charges when approving a road scheme; to sign a concession agreement containing cancellation charges before a scheme was approved; and to refuse to make public a concession agreement affecting the environment.
FoE said that, before the general election, Labour promised it would not build the road because noise and air pollution would harm the health and amenities of residents. But soon after the party came to power, the road was given the go-ahead.
Gerald Kells, of West Midlands FoE, said: "The Government has already broken its promise not to build this road. Now it appears to be preventing people from having access to the facts behind it. If the Government has nothing to hide, then it should come clean and produce the documents."
FoE says the road will cut a huge swath through the West Midlands green belt and cross two protected nature sites, destroy scores of homes and blight many others.Reuse content