MORE than 17,000 homes could be built on Oxford's Green Belt, with the protected land facing an 'unprecedented' threat.

The scale of what is proposed has been laid bare for the first time in new analysis produced by the Campaign to Protect Rural England (CPRE).

It shows a series of massive potential developments on the edges of the city, which are proposed in draft Local Plans by councils.

These include sites that could be earmarked for 4,400 homes around Kidlington by Cherwell District Council.

Others proposed in South Oxfordshire total 9,000 homes, but the district council has not yet decided which ones it will formally propose to take forward.

Potential developments are proposed south of Grenoble Road, between Cowley and Horspath, at Wick Farm, at Thornhill Park and Ride and at Wheatley.

Meanwhile, several other sites have been suggested in technical studies or schemes brought forward independently by developer.

Countryside campaigners have pointed the finger at Oxford's colleges and other major landowners, claiming they will reap the rewards of a 'financial bonanza' if building is allowed on the Green Belt.

Helen Marshall, CPRE's Oxfordshire director, said: "We need to stop this gravy train before it leaves the station.

"These attacks are unprecedented in the history of our Green Belt, which is designed specifically to protect our historic city from urban sprawl of this kind.

"It shows the flaws in the argument of allowing small parts of the Green Belt to be opened up to development – it is clear the merest whiff of an opportunity gets all the vultures circling.

"The colleges will claim altruism, but we don’t believe this will make any difference at all to those in housing need.

"The houses proposed are very unlikely to be genuinely affordable. In fact it is basic property speculation and will deprive existing local communities of access to the countryside and impact on their quality of life in other ways."

The proposals for housing are emerging as local authorities scramble to agree how they will deliver thousands of new homes, in response to a report published in 2014 that said 100,000 were needed by 2032.

Of these, about 28,000 are needed to meet demand in Oxford but only space for about half will be delivered within its boundaries.

This is because Oxford City Council says it does not have enough space. It has asked neighbouring authorities to shoulder the other homes between them, calling for development to be allowed on the Green Belt.

However, campaigners claim it will lead to the 'urban sprawl' which the Green Belt was created to prevent.

Ms Marshall said more should be done to re-use brownfield land – sites already built over – such as Osney Mead industrial estate and developments made to a higher density.

But Alex Hollingsworth, the city council's executive board member for planning, said it was not possible to deliver all the homes needed in the city within Oxford's boundaries.

And he rejected claims that Green Belt changes were 'unprecedented'. The city council has jointly put forward proposals for a 3,500-home 'science village' on land south of Grenoble Road with Thames Water and Magdalen College.

He said: "It is simply not true to say the Green Belt is sacrosanct.

"It is reviewed on a regular basis and there have always been adjustments and changes.

"The case for reviewing the Green Belt now is one driven by the clear need for more housing. That is not to say we think it should be a free for all – each site must be assessed on its own merits.

"Our view is there should not be a blanket refusal to consider development there or a blanket acceptance."

Mr Hollingsworth said he believed the massive demand for housing qualified as the 'exceptional circumstances' needed under national planning rules to build on the protected land.