The ITV Tonight documentary also contains claims by an executive who masterminded the original rail contracts system that the cost of the blunder will far exceed the £40 million estimated by Government.
Chris Stokes, former Deputy Director of Franchising at the Department for Transport said:
I would guess that bidders for other franchises will claim back the costs of their bids as well, so yes I think it’s likely that it may well be £100 million.
Government plans to take the West Coast Mainline away from Virgin were reversed earlier this month, after "serious defects" were found in the process.
Three civil servants have been suspended and two official reviews launched.
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The Labour leader did not say whether he would maintain Britain's nuclear deterrent programme.
Ukip leader Paul Nuttall also said he would want to get rid of Sharia courts.
Over 40,000 people picked up their packs to take part in the annual marathon in the capital.