Rail travellers will face delays on journeys between London and Birmingham from Saturday as a stretch of track is shut for upgrade work.

Operator Chiltern Trains is installing a second track over a nine-mile stretch of the line between Banbury and Bicester North in Oxfordshire.

The �60m work will mean the line will be closed for 17 days until 6 May.

Services will be diverted through Oxford and will take an extra 20 minutes.

There will also be replacement bus service running every 15 minutes between Banbury and Bicester North.

Chiltern said converting the line to a double track would remove a bottleneck which currently caused delays to services along the whole route.

A spokesman said: "Inevitably projects of this magnitude do cause substantial disruption to services."