London's Crossrail delayed again and to cost even more

A construction worker wears a branded jacket at the site for the Crossrail station in Tottenham Court Road London

A construction worker wears a branded jacket at the site for the Crossrail station in Tottenham Court Road London

On this basis, the new delay could cost hundreds of millions of pounds, particularly if the scheme misses its new projected opening date of 2021.

Transport for London said on Friday it had now been notified that the line would not open until 2021.

Crossrail bosses waited until last August - fewer than four months before the line's scheduled opening - to admit that they needed more time to complete the fitting out of the central tunnels and to develop key software packages for the railway. The bulk of the delay this time is being blamed on the "software development for the signalling and train systems" and safety approvals processes, although the positive news is that test runs running over the full line should start in 2020, so it will happen at some point and is not going to be revoked, backfilled and forgotten about. It is in discussions with Crossrail about how to fund the additional costs.

The cost forecast for the central section of the line has risen to about £15.36bn - £400m more than the funding committed under a financing package agreed with the government.

Then in December 2018, TfL announced a new financing package provided by the Department for Transport (DfT), the Greater London Authority and itself to support the final stages of the project. "By the end of the year, Custom House, Farringdon and Tottenham Court Road stations will be complete and the project is on track to finish fit-out of the tunnels in January", he said.

"Small businesses along the route of the Elizabeth Line, from Berkshire to Essex and across London, have always been preparing for the start of the service in early 2020".

Known officially as the Elizabeth line, the project was allocated £14.8bn in 2010 which eventually swelled to £17.6bn with the latest increase pushing it beyond £18bn. "The Trial Running phase will begin at the earliest opportunity in 2020, this will be followed by testing of the operational railway to ensure it is safe and reliable".

"TfL has been advised by Crossrail Ltd that their latest assessment is that the opening of the central section will not occur in 2020, which was the first part of the previously declared opening window", TfL said.

Wild said he expected to provide Londoners with "further certainty" about when the line would open "early in 2020".

Mr Wild said he wants to "ensure reliability of the railway from day one of passenger service".