The southbound lanes were closed while the crash was cleared

Two lorries and a car transporter collided on the A34 near Oxford.

The crash on Tuesday closed the road and prevented thousands of people from reaching Oxford, reducing custom in city centre shops.

Oxford's chamber of commerce president Keith Slater has put the combined cost to trade at �5m to �10m.

We're very much in favour of something being done about the A34 Keith Slater Oxford Chamber of Commerce

The crash happened at 0430 GMT and the southbound carriageway finally opened at 2200 GMT.

The car transporter driver remains critically ill in hospital, while the other two drivers were also taken to hospital with minor injuries and shock.

Mr Slater said: "If you look at all the aspects of the crash - the people involved, the vehicles involved - the emergency services' time - the loss of sales, we could be talking about �5m to �10m as the result of that one accident.

"The centre of Oxford was quite quiet for this time of year, especially from mid-morning.

"Takings in many stores were down something like 10%."

Important route

AA spokeswoman Rebecca Rees said thousands of drivers were caught in the queues.

"As well as problems on the A34 itself, the A40 was jammed solid and the A420 saw tailbacks of more than seven miles," she said.

"The A34 is one of the most important routes in the country, connecting the south coast with the Midlands. It carries more traffic than it was designed for, and has no hard shoulder.

"As a result, when accidents occur, there is no emergency lane to clear the wreckage to."

Mr Slater said the Chamber of Commerce had been calling for the A34 to be upgraded for some time.

"We're very much in favour of something being done about the A34.