MPs from the Commons public accounts committee have called for the Department of Transport to provide more detailed evidence to support the estimated £50 billion investment. Presenting the committee's findings, chairperson Marget Hodge said:
The pattern so far has been for costs to spiral - from more than £16 billion to £21 billion plus for phase one - and the estimated benefits to dwindle.
In my committee's experience, not allowing enough time for preparation undermines projects from the start.
More top news
Batsman Phil Hughes died after a "catastrophic" head injury caused by a cricket ball splitting a major artery at the base of his neck.