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.
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