The Metropolitan line extension has been left out of the Mayor of London's new plans for transport - for the second time.

Mayor Sadiq Khan has set out his long-term plans to improve the tube, DLR, rail, tram and bus services across London, with a focus on lowering emissions and creating jobs until 2050.

SEE ALSO: Metropolitan Line Extension: Everything you need to know about the project

However the Met line extension to Croxley has been left out of plans despite mentions to improvements on most other tube lines, extensions to the Northern and London Overground lines and the opening of a new Elizabeth line.

London’s Transport Commissioner, Mike Brown MVO, said: “This ambitious strategy for the next 25 years sets out how we will invest in modernising and improving our services so that people have excellent transport connections no matter where they are in the city."

Concerns over the Met line extension were first brought to the fore after a letter from TfL’s head of London rail investment and LU line extensions Robert Niven to Conservative London Assembly member Gareth Bacon revealed the Department for Transport left a £50 million gap in funding for the extension.

SEE ALSO: Have plans to extend the Metropolitan Line derailed?

The mayor has also said he hopes all transport in London will be zero emissions by 2050,with buses to reach this goal by 2037.

A spokesperson for the Mayor of London did not give a new statement regarding our questions over whether the Mayor of London will be seeing to the extension.

Richard Wood said: “This project is outside London and therefore responsibility for delivering it ultimately lies with the government.

"The previous Mayor committed £49 million of London taxpayers money to delivering it without properly working out how much it would cost.

"Since then, estimated costs have spiralled by at least an additional £50 million.

"TfL are happy to discuss with the government how this funding gap can be filled, but as this scheme is outside London it is not right that London taxpayers should have to pay even more towards it. London taxpayers would expect nothing less."