Sadiq Khan has accused the Government of “plucking out of the air” the promise to build up to 10,000 new homes at Euston.
The mayor said that the pledge - made last week as prime minister Rishi Sunak announced the scrapping of HS2’s northern leg - had been made without full consideration of the practicalities.
The Government insists its plans represent “a world class regeneration opportunity”, which will draw on the success of similar schemes elsewhere in the capital.
Speaking at a Mayor’s Question Time session on Thursday, Mr Khan said: “New homes are welcome, as long as they include good levels of genuinely affordable homes.
“But this figure seems to have been plucked out of the air, with no consideration of local planning constraints, or existing proposals for the expansion of the life sciences sector in the area.”
The Government has pledged to create a new ‘development corporation’ to oversee the project.
The mayor said: “I'm concerned that the development corporation is just a smokescreen to distract from the chaos of the Government's intervention and remove powers from local communities."
Mr Khan also repeated some of his other concerns in relation to the completion of HS2, which he raised in a letter to Mr Sunak on Friday of last week.
He told the London Assembly he was worried by the PM's decision to withdraw all public funding from the section of the route between Old Oak Common and Euston, instead relying on private investment.
The mayor claimed this could "result in the Euston terminus being cancelled by stealth", and that the Government should, at the very least, "commit to step in as the funder of last resort".
He added that the prolonged usage of Old Oak Common as the line's temporary terminus would require a re-design of the station, because it would mean trains would need to be turned around there.
"Last week's announcement creates more uncertainty and delay at Euston and adds further urgency to the need to resolve the issues at Old Oak," he said.
Responding to the mayor’s comments, a Government spokesman said: "As we have always planned, the new line will finish at Euston – that has not changed.
"The new plan for Euston represents a world class regeneration opportunity, and the strengths of this approach are evidenced by recent developments at Battersea and nearby King’s Cross.
“There is already support and interest from the private sector and Ministers have had discussions with key partners since the announcement."
