London mayor Sadiq Khan said he was "disappointed" that the government didn't back Crossrail 2 in today's Budget.
While the mayor said he was pleased to see progress on devolution, other areas were notably missing from Philip Hammond's announcements.
“London did not get everything we needed today," said Khan. "I am disappointed that the government did not use the opportunity to fully fund our police force or pledge their support for Crossrail 2."
A new London Devolution Agreement will though, he said, help London "protect jobs and investment in the aftermath of Brexit".
Devolution to the capital includes infrastructure, where London will pilot a new development rights auction model for funding future projects and will provide significant funding towards future projects, allowing them to be built quicker.
The mayor and Transport for London (TfL) will also be given new powers to reduce congestion.
The lack of mention on Crossrail 2 came as London Assembly members today passed a motion urging the government to crack on with Crossrail 2, saying the capital’s transport network will "grind to a halt" without it.
The Assembly said at least 17 Underground stations will buckle under crowding pressures should the government neglect the project. It agreed a unanimous motion asking the Transport secretary to approve Transport for London’s (TfL) strategic outline business case for Crossrail 2 without delay.
Caroline Pidgeon, who proposed the motion, said it was "incredibly concerning" that the chancellor could set out his plans for infrastructure "but completely fail to mention the huge need for Crossrail 2".
Crossrail 2 is vitally needed to relieve congestion on busy routes into central London and support economic development in and around the capital.
It would also create better connections across the South East and the whole country. We cannot afford for the scheme to be delayed or held back.
We have waited over 40 years for Crossrail. A similar wait for Crossrail 2 would be a disaster.
There has been concern that the government's interest in the project has been waning and that the North-South rail link might be overlooked in favour of HS3, though neither were mentioned during the Budget.
Florence Eshalomi, who seconded the LA motion, said: "We know that without Crossrail 2, London’s transport system could grind to a halt. Given that HS2 will put even more pressure on the network, particularly at Euston where the line terminates, it is vital that the secretary of state for transport approves the Crossrail 2 scheme without delay."
Crossrail 2 would serve stations throughout the south east, linking south west and north London, as well as Surrey and Hertfordshire.
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This Assembly said that Crossrail 2 wouldn't just boost the capital. Some 40 per cent of the transport benefits and 30 per cent of the new housing would be delivered outside London.