Track improvements that have closed the railway line between Banbury and Bicester are progressing well, say Chiltern Railways and Railtrack.

The work is being done to improve reliability and punctuality of services between Banbury and London by dualling the only section of single track on the route.

The doubling of the track will help Chiltern Railways run more frequent services and increase the punctuality of trains between Birmingham and London which call at Banbury, Kings Sutton, Bicester North and Haddenham and Thame Parkway.

The line from Aynho junction to Bicester has been closed completely, and will remain out of use until May 6.

There will be no trains between Bicester and Banbury during this period. Chiltern Railways is working closely with other train operators, especially Thames Trains, to provide alternative services to London, and has promised passengers that the benefits of the work will outweigh short-term inconvenience.

During the track closure, Chiltern's peak service trains will run via Oxford to Paddington and back, and journey times to and from London will be about 20 minutes longer than normal.

Additional peak and off-peak connections are available to and from Paddington -- passengers will need to change at Oxford for a Thames Trains service. For local trips, buses will run every 15 minutes between Banbury and Bic- ester North. Passengers who normally drive to a station are advised to use Haddenham and Thame Parkway, just off junction 8A of the M40, for southbound journeys.

The line will re-open in May and testing of the track will continue at night and over weekends until mid-August. This will also cause some changes to normal services and passengers are advised to check before travelling. Travel updates can be found on the website www.chilternrailways.co.uk or by calling 08705 165 165.