The government has last week abandoned plans to use private funding to pay for the £1bn rolling stock contract in favour of public funds to ensure the project starts on time.
The change was allegedly made to simplify contract negotiations and ensure the trains can be ordered by mid-2014 ahead of planned testing in 2017.
“In considering these concerns and the importance of the Crossrail project to the country, the government has been convinced that – in this specific case – a change in the financing strategy is an appropriate course to pursue,” said transport minister Stephen Hammond.
Funding for the £1bn project was also expected to be underwritten by the UK Guarantees programme.
The announcement was condemned by shadow transport secretary Maria Eagle.
“The government must come clean and admit how much tax-payers money was wasted on the abandoned model of procurement and whether they will be forced to compensate bidders for their own additional costs,” said Eagle.
The Department for Transport stated that it would continue to use private finance on other projects.