The Department for Transport is struggling under Treasury pressure to rein in spending on the railways, according to the FT.

With the latest ministerial review of rail policy yet to take effect, the department's bill for subsidising the privatised network is currently running at £5 billion per year.

Four per cent more passengers are using trains every year.

Meanwhile, ministers are set to quiz the manufacturer of Sir Richard Branson's new pendolino trains.

The government wants to know why the trains, made by the engineering company Alstom, are between 14 and 20 times more likely to break down than similar rolling stock on the continent.