PARTS of Oxford's Green Belt must be used for new houses to help tackle the city's lack of affordable homes, leading estate agents have warned.

According to property analysts Hometrack, house prices in Oxford have risen yet again and in the past year the average price has gone up by 9.2 per cent to £430,200.

Separate data released by Lloyds Bank showed that Oxford remains the least-affordable city in the country outside London, with the average home 10.7 times more than the average household's earnings.

National planning guidelines say the Green Belt can only be built on in exceptional circumstances.

But Mark Charter, head of Carter Jonas's Oxford office, said the lack of remaining brownfield sites in Oxford meant land from the Green Belt needed to be released for new housing.

He added: "That would not necessary bring down the price of properties but it would provide more homes at entry-level prices of about £300,000."

Mr Charter said you could buy a two-bedroom apartment in Grandpont or East Oxford for about £375,000 or a one-bedroom apartment in the city for about £200,000.

He said: "More and more buyers are being forced to look outside Oxford because properties are so expensive.

"We have mapped where our Oxford employees live and it covers a wide area including Gloucestershire, Wiltshire, Berkshire and Northamptonshire.

"They drive in and then use the park-and-ride."

Rowan Waller, managing director of Wallers of Oxford estate agents said building on the Green Belt 'has to be part of the solution'.

He said: "I don't want to get rid of great-crested newts any more than the next man but building on the Green Belt must happen relatively soon.

"We have to stop thinking of the Green Belt as a pretty part of the countryside and realise that some parts are ugly wasteland that could be built on."

For 17 years the city council has been lobbying to build new homes on Green Belt land within South Oxfordshire District Council.

It wants to build a total of 7,500 homes off Grenoble Road but last year Chalgrove Airfield was chosen by SODC as a preferred strategic site.

A city council report said last year that a total or more than 12,000 homes could be built on protected Green Belt land surrounding Oxford over the next 15 years.

But the Campaign to Protect Rural England in Oxfordshire said the homes should not be built on the Green Belt because it would lead to a 'Greater Oxford' and increased traffic congestion.

Mr Charter said new housing types and models including 'pod' homes should also be considered.

But earlier this month, city councillors rejected plans for the first 'smart homes' to be built in the city.

Developers Openwell put forward plans for 70 low-cost apartments in William Morris Close, Cowley, costing about £160,000 each, to target key workers and first-time buyers but council officers recommended refusal because the land is earmarked as open space in the Local Plan.

Last month CALA Homes started building 12 homes off Abbey Road, West Oxford, with half affordable homes and half costing £1m each.

The average home in London is still the highest in Britain at £486,600, and the cheapest major city is Glasgow at £115,200.