The new Tube line is in the dress rehearsal phase before being opened to passengers next year, Transport for London (TfL) said.

The line is currently in the experimental phase, in order to ensure the safety and reliability of the railway for public use and to test the schedules.

Transportation agencies and emergency services will perform 150 scenarios over the next few months, including exercises to ensure staff can respond to incidents, including sick customers and signal failures.

The most complex exercises include evacuations of trains and stations with thousands of staff and volunteers, before a period of “shadow running” which means that the line operates without passengers.

The Mayor of London, Sadiq Khan, said the testing phase marked a “milestone” in the delivery of the Elizabeth Line, which will boost the economy of the capital.

Mr Khan added: “The next few months are crucial in ensuring that the railroad can safely open next year, and everyone is working incredibly hard to achieve this goal.

“The Elizabeth Line will help transform travel in London and the South East, dramatically improving transport links, supporting regeneration and boosting our economic recovery. “

The launch of the Elizabeth line was led by Crossrail’s board of directors until October 2020, when governance was transferred to TfL.

Crossrail chief executive Mark Wild said the line is set to open in the first half of 2022, although no exact date has yet been given.

He said: “This is an extremely complex railway and we have to be able to demonstrate the highest levels of reliability.

“Everyone is working hard to deliver the Elizabeth line as soon as possible and we remain on track to start passenger services in the first half of 2022.”