THE M40 northbound has fully reopened between Bicester and Ardley after a four-vehicle crash which caused major delays. 

Lane three of three on the southbound carriageway was also shut earlier on Tuesday afternoon but has now reopened.

Thames Valley Police confirmed two crashes had taken place in the afternoon in quick succession, with the first involving a van that crashed into the central reservation north of junction 9 at 12.23pm.

The force said four vehicles had then been involved in a separate incident at 12.28pm, which saw the northbound carriageway closed completely.

Police spokeswoman Lucy Billen said no one had been seriously injured and the carriageway was clear of obstructions as of 1.50pm.

She added: "However, we would still advise drivers to expect delays."

There were also knock-on delays for drivers on the A34, with northbound traffic between Bicester and Oxford queuing for several miles.

Highways England said it expected normal conditions to resume from 2.45pm. 

Bus operator Stagecoach early in the afternoon said all its Bicester services were being diverted and that its Wendlbury A41 bus stop was not being served.