A busy park-and-ride could be extended following complaints that motorists are leaving their cars on a nearby estate.

Transport chiefs are drawing up plans to extend Thornhill Park-and-Ride and hope to submit a planning application next year.

People living in the nearby Sandhills estate claim commuters are parking outside their homes when the site is full - making it difficult to access their driveways or find space for visitors.

And they complained that redevelopment work at Thornhill was limiting space for commuters and time restrictions at the site meant many were choosing to park in Sandhills instead.

One resident, who asked not to be named, said the problem had got much worse recently.

She said: "Apparently some of the people, if they ask where the overflow car park is, are being directed over here. It's just annoying."

The mum-of-two said she would like to see the park and ride expanded. She added: "I don't really want a controlled parking zone if you have to pay for it. At the end of the day it's not our fault."

Oxfordshire County Councillor Roz Smith and city councillors Patrick Murray and Chris Scanlan distributed 350 surveys to local people last Saturday to discover the extent of the problem.

Mrs Smith said Thornhill Park-and-Ride could not cope with commuters travelling to both London and Oxford city centre.

She said: "County staff on that site are directing people to park in Sandhills if there isn't any space.

"People are fed up. With Thornhill you can only park there 72 hours maximum so people going to Heathrow, Gatwick and London for a week are parking in the Sandhills.

"It's outrageous."

Mr Murray said 52 of the surveys had been returned so far, with more still coming in.

Mr Murray, councillor for Barton and Sandhills, added many residents also supported having signs warning against park and ride commuters leaving their cars in Sandhills and a 30-minute waiting restriction outside the local school.

He said he would now be taking up the issue with officers from Oxfordshire County Council.

Oxfordshire County Council spokesman Paul Smith said work on a new building with a waiting room and toilets at Thornhill was due to finish later this month but more space was still needed.