Campaigners hoping to win a court battle to stop flats being built on green space have accused Barnet Council of putting the case “in the hands of the developer”.

Finchley Memorial Action Group, which wants to protect an area of green space next to Finchley Memorial Hospital, claimed the council had delayed taking action that would have helped the campaign group’s legal challenge.

The group says the council failed to call a committee meeting to formally admit its decision to grant permission for the development was unlawful in advance of a High Court hearing next week. The council says any decision by the committee would not have stopped the hearing from taking place or prevented the court from determining the matter.

Community Health Partnerships (CHP), which is owned by the Department of Health and Social Care, won outline planning permission last year to build 130 flats in four blocks ranging from four to five storeys on green space south of Granville Road and east of Bow Lane. The council’s strategic planning committee approved the scheme, which is designed to provide homes for NHS staff, despite hundreds of objections from local residents.

Earlier this year, a judge granted a judicial review of the decision, and a court date has been set for Wednesday and Thursday this week (October 5 and 6). The legal challenge was brought by Finchley resident Jennie Arthur, who argues the planning permission was not lawful.

Jennie and other campaigners claim the council failed to take proper account of local and national planning policies. They also claim the council made a factual error regarding salary bands for NHS staff.

Barnet Council has since stopped defending its decision to grant permission. But the campaigners say it has left it too late to “consent to judgment”, which would have meant formally admitting its decision was unlawful. The developer subsequently applied to the court to take over the case and will face campaigners in the judicial review hearing.

The council’s constitution means the same body that made the planning decision must agree to consent to judgment. But it needs to provide the public with two weeks’ notice of a meeting of the strategic planning committee, meaning a meeting could not be convened before the court date.

Finchley Memorial Action Group says the council knew about the situation in July and pointed out that Labour’s local election manifesto included a pledge to protect green spaces.

Christina Welch, a leader of Finchley Memorial Action Group, said: “We are appalled, very disappointed and feel let down by both council officers and our elected representatives. How could they leave it so late?”

The campaign group accused the council of “heaping financial pressure on the community at a time where the cost-of-living crisis and rising interest rates are already beginning to bite”. The group, which launched a crowdfunding campaign to raise money for the legal challenge, says that if the community wins the case, the council will have to pay 80 per cent of its costs.

A council spokesperson said: “Planning permission was granted in December 2021. An application for judicial review has been made and there is a court hearing planned for the beginning of October. In this situation only the court can quash the decision to grant planning permission.

“Any decision by the strategic planning committee relating to the planning consent prior to the court hearing would not have stopped the court hearing from taking place or prevented the court from determining the matter before it. While the council has decided not to defend the claim, the interested party is defending the claim as is their right to do.

“The council could not have quashed the planning permission itself or short-circuited the hearing at any time and now awaits the decision of the court. In the meantime, the council’s administration is focusing on ensuring that public green spaces are protected from development.”

A CHP spokesperson said: “As a Department of Health and Social Care company and part of the NHS family, Community Health Partnerships remains committed to deliver the affordable homes for NHS staff project in Finchley. We are convinced of the crucial benefits to the local health system and patient care and have a unique opportunity to address a significant challenge faced by our NHS partners.

“The project will provide up to 130 high-quality, affordable, homes for staff at a time when housing affordability poses enormous recruitment and retention challenges for the NHS in North London.”