THE heavily delayed Crossrail is now expected to open in summer 2021, according to the project's chief executive.

The troubled railway, from Berkshire to Essex via central London, was originally expected to open in December 2018 but repeated delays have pushed it back.

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Earlier this week, the outgoing commissioner of Transport for London said it is expected to open in autumn 2021.

But on Friday, Crossrail Ltd confirmed it plans to open the central section between Paddington and Abbey Wood in summer 2021.

It is hoped that full services across the Elizabeth Line from Reading and Heathrow in the west to Abbey Wood and Shenfield in the east will then commence by mid-2022.

Mark Wild, chief executive at Crossrail Ltd, said: "We have a comprehensive plan to complete the Elizabeth Line and the milestones we must hit during 2020, including the testing of the signalling and train systems and safety assurance, but there are no shortcuts to delivery of this hugely complex railway.

"Our latest assessment is that Elizabeth Line services through central London will commence in summer 2021, but we are aiming to open the railway as soon as we can.

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"This forecast assumes a period of time will be required to undertake intensive operational testing.

"The key focus for everyone on the Crossrail project is commencing intensive testing of the Elizabeth Line as soon as we can in 2020, to enable passenger service as early as possible in 2021."

Crossrail's budget was set at £15.9 billion in 2007, but it is now expected to cost an estimated £18.25 billion.

After the original December 2018 date was missed, a plan to open between October 2020 and March 2021 was announced in April 2019.

TfL has lost between £500 million and £750 million in passenger revenue due to the delays.