Hackney Green Party protested outside the town hall last week over the protracted redevelopment of the Woodberry Down Estate.

The flagship project, which began in 2009, is set to enter its third phase - but the campaigners say the loss of social homes is doing nothing to solve the housing crisis.

Hackney Council acknowledges there will be a loss of about 320 social homes on the estate once the project is finished. Remarkably, poor record keeping means the council doesn't know exactly how many there were at the point of demolition, but it is estimated at about 1,586. There will be 1,264 on the new estate, with another 1,110 for shared ownership.

Tyrone Scott, a housing advisor and Green campaigner, said: "As we prepare to celebrate the 100th anniversary of council housing, I find it heartbreaking that I am having to demonstrate on the steps of Hackney Town Hall to stop our council from continuing this development which will lead to a further reduction in the amount of council homes.

"Hackney Council needs to wake up to the fact that this development is not delivering what it promised to do."

The council says the Woodberry Down project was dreamt up in a different time, but says the idea was always to improve the estate as a whole.

That is in contrast to the town hall's in-house project to build 2,000 homes, three schools and a leisure centre across Hackney in the next four years, with a net increase of social homes.

Mayor Phil Glanville said: "Construction began in a period when councils were essentially prevented from directly building homes and went on site for delivery in the teeth of the recession between 2008 and 2009.

"While the project is being delivered by a strong partnership of the council, Berkeley Homes, Notting Hill Genesis and local residents - rather than directly by the council - it is delivering significant benefits for the community.

"As well as a new, modern home at a social rent for every existing secure council tenant, the project has already delivered a new community centre, secondary school, and parks, alongside the reopening of the stunning Woodberry Wetlands for the first time in nearly 200 years."

Mr Glanville said the council would look to improve on the 41 per cent promise for social rent and shared ownership homes as phase three progresses.