Mayor of London Sadiq Khan has told the government’s spending watchdog that Crossrail will need additional cash before it is completed.

Writing to the National Audit Office (NAO), Khan said that further funds will be required despite the mayor’s office releasing an additional £300M for the project and the government loaning a further £350M in recent months.

Khan also expressed “serious concerns” about whether Crossrail’s management “was fit for purpose” in the letter reproduced by the Financial Times.

“While I agreed £300M additional funding with the government […] we now know that the scale of the issues faced was in fact much greater,” Khan wrote.

“With the latest revelations about the project’s cost and schedule continue to have significant concerns over transparency on the project and the effectiveness of Crossrail’s governance, strategic risk management, commercial arrangements and assurance regime.”

The National Audit Office is undertaking its own review into Crossrail after a year-long delay to the £15.4bn project was announced in August.

Khan previously announced that he only knew about the delay two days before it was made public.

Earlier this month New Civil Engineer revealed a new timeline for works and testing on the line.

The line was originally scheduled to open this December. The central section of the line is now due to open next autumn, with the full service with trains running from Reading in the west to Abbey Wood and Shenfield to the east unlikely to begin until 2020.

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