The devastating floods that swept through Oxfordshire last July were a freak event unrelated to climate change, according to a new report.

Researchers at the Centre for Ecology and Hydrology claim the River Thames and its tributaries are no more likely to flood today than 100 years ago.

But they did admit the impact of flooding has increased and warn against building more houses on the county's flood plains.

Author Terry Marsh, from Wallingford, said record levels of rainfall in Oxfordshire last summer did not fit with trends towards drier, hotter summers and wetter winters expected under climate change models.

He said: "We can find no trend that flooding along the River Thames is getting worse and we have records dating back to 1883.

"The 2007 floods do not form part of any long-term trend or part of any emerging pattern that conforms with climate change scenarios. We have an inherently capricious climate and on occasion you get extraordinary events."

But Oxford-based author Mark Lynas, an expert on global warming, said: "The scientists have missed the bigger picture.

"They have concluded it was a freak event, but climate change suggests we are more likely to experience freak events."

He added: "This was the heaviest rainfall in the shortest period of time on record and it seems to me that relates decidedly to climate change."

Mr Marsh did, however, warn that people's vulnerability to flooding had increased because of development on flood plains. Thousands of properties in Oxfordshire were flooded last July, including the home of Nick Gladwin, in Earl Street, Oxford.

He said over-development was the main cause of flooding in West Oxford.

He said: "We have been a bit scared into thinking we are going to suffer flooding every day of the week.

"It could happen again in a few years or in 50 years."

Alison Campbell, 40, whose Abingdon home was damaged by flooding, said: "I think it was just a freak. It was just down to the amount of rain we had that day."

The Environment Agency did not attribute last summer's floods to climate change but warned of more extreme weather events, such as flooding, in the future.