Crossrail, the organisation in charge of building London’s new Elizabeth line, has pushed back the 10-year mega project’s official opening date from December 2018 to autumn 2019.
Chief executive Simon Wright said more time is needed to complete testing on the central section between Paddington and Abbey Wood.
“The Elizabeth line is one of the most complex and challenging infrastructure projects ever undertaken in the UK and is now in its final stages,” he said.
“We are working around the clock with our supply chain and Transport for London to complete and commission the Elizabeth line.”
The original testing programme was delayed as contractors needed more time to complete the fit-out of the central tunnels and the development of rail systems software, according to Crossrail.
Testing has started but further time is required to complete the full range of integrated tests.
Elizabeth line trains are already operating between Shenfield and Liverpool Street and between Paddington and Hayes & Harlington. The trains are also being tested in the Heathrow tunnels.
Construction activity is drawing to a close including the completion of the remaining architectural fit-out in the new central section stations.
Crossrail estimates that the Elizabeth line will add 10 per cent to central London’s rail capacity and boost the economy by an estimated £42 billion.