New high-speed rail line HS2 will cost £160 billion to build in full, claims a Midlands MP.
Conservative member for North West Leicestershire Andrew Bridgen told Parliament he had received information from whistleblowers that the cost of the project could spiral to around £50 billion above previous estimates.
He also said the first phase of the line between London and Birmingham would not open until 2041 which is around a decade later than the current plan.
The MP claimed this information had come from insiders within HS2 Ltd, the Government-owned business building the line, and the Department for Transport but the latter has insisted his figures are wrong.
The overall vision for HS2 line is to run between Birmingham and London (phase one), Birmingham and Crewe (phase 2a) and Crewe and Manchester and Birmingham, the East Midlands and Yorkshire (both phase 2b).
Recent reports have suggested the eastern leg of HS2 to Yorkshire is in doubt.
Speaking in a debate in Parliament, Mr Bridgen said that phase one, which has an official budget of no more than £44.6 billion, would in fact cost £70 billion.
He said: "Phase one is already £70 billion and the enabling works are running massively over budget.
"They are being suppressed and that is going to be thrown into the main budget at the end."
A review by former HS2 chairman Douglas Oakervee concluded in early 2020 that the cost of HS2 could be up to £87.7 billion in 2019 prices.
One independent estimate put the cost at £106 billion but this finding was rejected by the Oakervee review.
All of the previously estimated costs, however, are significantly lower than the £160 billion suggested by Mr Bridgen.
He said: "I have been sent 85 megabits of statements from whistleblowers inside HS2 and the Department for Transport which indicates phase one will be unlikely to carry passengers before the year 2041.
"We are going to need a public inquiry ultimately to get to the bottom of who was suppressing all this information."
A Department for Transport spokesperson said: "These figures are wrong. In February last year, this Government reset HS2 and established a realistic budget, strengthened oversight and increased transparency.
"As part of this, a minister now reports to Parliament every six months on progress, including on costs and schedule."
