Chiltern Railways remains the county’s most punctual train operator, according to Network Rail figures.

Last month, 94.9 per cent of Chiltern’s services ran on time, down slightly on the 95.4 per cent recorded a year earlier, but ahead of the national figure of 93.7 per cent of trains on time, which was the same as in 2010.

Chiltern, which operates trains from Banbury, Bicester North and Haddenham & Thame Parkway to London and Birmingham, will launch a speeded-up timetable from September.

CrossCountry, which links Oxford and Banbury with the West Midlands and the South Coast, saw performance improve from the previous year, with 92.2 per cent of services on time, up from 91.3 per cent.

First Great Western, which links the Cotswold Line, Oxford, and Didcot to Reading and London, operated 92 per cent of its services on time, down from 93.8 per cent in May 2010.

The most disruptive incident nationally last month was a major signal failure between Reading and Twyford on Monday, May 9, which led to the cancellation of 139 FGW services and caused almost 6,000 minutes of delays.