Birmingham City Council is being called on to cancel the sale of a former school and playing fields for housing after it emerged a deal with a developer had been signed in secret two years ago.
Residents and councillors have so far been successful in stopping plans for housing on the Martineau Centre site, in Harborne, but developer Persimmon Homes has lodged an appeal which is to be heard in October.
Now it has emerged that the council's property division sold the site to Persimmon in 2012, subject to planning permission being granted, and if the appeal is successful the council is contractually bound to hand over the site.
Last year, the council's planning committee threw out proposals for 129 homes on the site saying that playing fields were in short supply in the area and calling for the school to be reinstated as there was a city wide classroom shortage.
The issue has become a key local issue prompting widespread opposition from residents groups and politicians on all sides.
Local Tories have blamed the Labour-run council for the sale in November 2012. But now Labour councillors are pointing out that the disposal of land was agreed by a previous Tory cabinet and followed through by officials, following negotiations with Persimmon, months later.
Campaigners now fear there could be severe financial penalties if the council pulls out of the sale and are pinning their hopes on a success at the planning inquiry.
Former Conservative councillor Peter Smallbone said: "The Labour Council fought tooth-and-nail to stop this contract being made public - it was only after local Conservatives appealed to the Information Commissioner that it was finally published.
"But large parts of the contract remain secret and we won't stop until the contract is published in full - or terminated."
Labour councillors have also opposed housing and are privately furious that officers carried out the sale behind the scenes without consulting them.
Coun Caroline Badley (Lab, Quinton) said: "The long-standing campaign against the sale of the Martineau is a cross-party community campaign.
"What we care about is winning this fight. What that means is working together, looking forward for every opportunity so that we prevail.
"Because once this green space and playing fields is gone - it is gone. All are welcome to join who share that vision."
Reacting to Tory rivals, she added: "They say the Labour council sold the Martineau. Actually, for those who care, council officers simply implemented a decision made by the previous Conservative administration earlier in the year."
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