Mayor of London Sadiq Khan has reaffirmed his commitment to the Metropolitan Line Extension, but said “someone” needs to stump up the additional £50 million needed to progress the project.

The £284 million development will connect the Metropolitan Line in Croxley to several new stations across Watford.

However there is some uncertainty about whether the project will go ahead as although previous Mayor of London Boris Johnson pledged £49 million towards the project, TfL cost projections show that a further £50 million will be required before construction work can begin.

​In a recent Mayor’s Question Time session, London Assembly member Shaun Bailey asked what needed to happen to make sure the project was delivered.

Mr Khan responded: “We are working with the council to bid for Government’s infrastructure fund. There is a shortfall of £50 million. If we can tap into that, also get local funders involved, we can get going on the extension.

“We are still committed to £50 million for the Metropolitan Line Extension and that is still there. The money promised is still there.  I am not resiling on that promise.  

“What has happened though is the cost of it is £50 million more, so my point is we will pay the £50 million we promised, but someone needs to pay the other £50 million.”

He added that he was “optimistic” the extension would go ahead, arguing the project had not ground to a halt simply because he was “sitting on his hands”.

Crunch talks on the extension have been arranged to take place between Mr Khan and Watford MP Richard Harrington on October 13.