DAVID Cameron has been accused by Labour of hoodwinking the electorate by holding back bad news over the "mess" in the running of Britain's railways until after the General Election.

The Conservative Government announced it was "resetting" a five-year £38bn railway investment programme, the largest since Victorian times, because Network Rail(NR) was behind time and over budget on a number of major projects.

The news came as Whitehall published its annual major projects report, which showed more than half the UK Government's top 188 schemes, with a price-tag of almost £490 billion, were at risk of failing, including the flagship Universal Credit welfare system and the High Speed 2 rail line from London to Manchester.

Labour urged the Government to call in the National Audit Office, the value for money watchdog, to undertaken an urgent review of Universal Credit, whose costs had risen by £3bn to almost £16bn, despite only 65,000 people claiming it.

In an emergency Commons statement, Patrick McLouglin, the Transport Secretary, told MPs that NR had admitted it had been "overly optimistic" about completing the multi-billion rail improvement plan.

Consequently, he told MPs electrification work was being "paused" on the Midland mainline and on the trans-pennine route between Leeds and Manchester.

Ed Cox, Director of the IPPR North think-tank, said the delays were troubling and would be a "major setback to the Northern powerhouse".

Mr McLoughlin also announced a shake-up of NR management with chairman Richard Parry-Jones being replaced by London's Transport Commissioner Sir Peter Hendy and that that none of the rail infrastructure company's executive directors would receive a bonus for the past year.

A spokesman for NR pointed out that about £2bn worth of projects had been paused and about 20 per cent of the company's overall expenditure plans were being reviewed.

But he stressed: "The vast majority of our work and hundreds and hundreds of projects across the country to improve and expand the railway continue."

The Government announcement came as Transport Focus, the rail customer watchdog, published a survey, showing train passenger satisfaction levels were falling.

Mr McLoughlin told MPs the problems NR had faced "could and should have been foreseen" and that in parts of its improvement programme the company's performance had "not been good enough"; much of the work needed on the railway should have been done decades ago, he stressed.

"Successive governments failed to invest the sums necessary in our rail network and that is why we find ourselves in the situation we are in today," he admitted.

But Labour's Michael Dugher insisted the Tories' broken election promises had been completely exposed and he accused Ministers of sitting on a report last September that had suggested the projects needed to be delayed.

"They have pretended to the public that everything was fine until after the election.Today is the day that the Government's failure to deliver a fit-for-purpose railway has been completely and so damningly exposed," said the Shadow Transport Secretary.

No 10, asked if David Cameron had been aware of the problems at NR before May's poll, declined to comment with a spokeswoman saying she was "not going to give a running commentary on process".