Stagecoach, the transport company which part-owns Virgin Rail Group, gave warning today that there was a significant risk that Network Rail would not be able to upgrade the West Coast Main Line in time for critical timetable changes due in December.

This is the first time the rail group has publically stated that it doubts Network Rail's ability to upgrade the main line from London to Glasgow by December, since the intervention of the Office of the Rail Regulator, which stepped in in January to vet Network Rail's plan of work.

It moved in after hundreds of thousands of Virgin passengers were left stranded over the New Year holiday and at Easter when Network Rail, failed to complete major engineering projects on time.

Stagecoach, which has a 49 per cent stake in Virgin Rail, alongside Sir Richard Branson's Virgin Group, said that Network Rail's recent operational performance on the West Coast Main Line had fallen short of its targets. The transport group said it continued to monitor developments carefully.

The company's comments came as it reported an 8 per cent increase in pre-tax profits to £174.4 million, up from £162 million and a 32 per cent increase in the full-year dividend.

Brian Souter, chief executive of Stagecoach, said: "We believe there are growing signs of a fundamental positive shift in customer attitudes towards public transport, driven by increasing road congestion, rising fuel costs and concern about climate change."

Times Recommends

• UK savers left in lurch as Icesave crumbles
• RBS shares close under £1 on bailout fears
• Asian stocks rebound on Australian rate cut