Go-Ahead's profits boost follows Arriva, National Express and Stagecoach reporting similar patterns.

National Express Group, which runs the East Coast line, recently said half-year pre-tax profits climbed 13.9 per cent to £90m. At the time Richard Bowker, group chief executive, said: "The public transport industry is seeing clear evidence that due to the rapid rise in petrol prices people are changing the way they travel in Britain."

Sunderland-based rail and bus operator Arriva last month said half-year profits were up to £66.3m from £47.3m a year earlier, and said it expects to see continued growth from "passengers looking to switch from more fuel-intensive car and air journeys".

When Stagecoach reported its annual results in June, pre-tax profits were up eight per cent to £174.4m, and the group cited research showing the cost of running a car has risen by 35 per cent in a year.