Campaigners calling on councils to cease building on the green belt say that more than 10,000 homes could be constructed on derelict or previously used land in Redbridge.

But Redbridge Council has said that – with a target of building 17,500 homes by 2030 – it cannot rely on brownfield sites alone to meet its housing needs.

Data from the council’s brownfield land register, analysed by the Campaign to Protect Rural England (CPRE), indicates that there is capacity to build 12,579 homes across 128 sites in the borough, covering 316 acres.

But the CPRE believes that confusion around the definition of “brownfield” means even more space could be available if eligible sites have been left off.

“Building on brownfield land presents a fantastic opportunity to simultaneously remove local eyesores and breathe new life into areas crying out for regeneration,” said Rebecca Pullinger, planning campaigner at the CPRE.

“It will help to limit the amount of countryside lost to development, and build more homes in areas where people want to live, with infrastructure, amenities and services already in place.”

A brownfield site is defined as land that “is or was occupied by a permanent structure”.

Eligible sites being left off the register could include land that is already in use, but could be altered to make space for housing, such as car parks, the campaigners added.

It has called on the government to force councils to prioritise brownfield development instead of building homes on green spaces.

A Redbridge Council spokeswoman said: “Our clear preference, as identified within the Local Plan, is to encourage developments on brownfield land over green space and/or green belt.

“Many of our brownfield sites are in town centre locations and we’re promoting their mixed-use development to support our broader regeneration ambitions.

“However, these sites alone cannot meet our housing requirements – the Local Plan targets 17,500 new homes up to 2030 and we are anticipating that this target will grow significantly with the adoption of the new London Plan.

“The Local Plan, which we widely consulted on and is subject to independent scrutiny by the planning inspectorate, therefore identified a number of other sites including some which we secured agreement to release from the green belt on the basis that it was simply not possible to meet our housing target without them.”

But opposition leader Councillor Linda Huggett (Con, Monkhams) insists that the council can meet its housing need without touching the green belt.

“There is enough land to build the homes we need without touching any green belt land in London and the same applies to Redbridge,” she said.

She added: “We also agree that there is confusion on the definition of the word “brownfield” and we are pleased [the CPRE] are nationally highlighting this important issue.”

She said that the borough’s green belt is “under threat” due to the Labour administration’s proposals to relocate three famous markets to a 162 acre site in Fairlop Plain.

“If this site was commercially developed on this massive scale it would break the greenbelt and would lead to further loss of greenbelt land in the future,” she added.

She also spoke of her party’s support for Hainault campaigners fighting an application to build 60 units of modular housing for the homeless in a park near Manford Way.

In 2017, the planning inspector blocked the council from building 850 homes on Oakfields playing fields in Barkingside, to the delight of campaigners.

Housing Minister, Kit Malthouse, said: “This government is committed to building the homes our country needs while still leaving the environment in a better state than we found it.

“We’re encouraging planners to prioritise building on brownfield land and working with local authorities to ensure sensible decisions are made on where homes get built.”

The Local Government Association has called for better resourcing for council planning departments, to ensure developers build homes as quickly as possible.