Sir Sadiq Khan has vowed to block Rachel Reeves's growth plans after the Chancellor gave the greenlight to an expansion at Heathrow Airport.
The Mayor of London, who has long opposed giving the UK's largest airport a third runway, warned the Chancellor he will look to halt her proposal by "whatever means we can".
Khan even hinted at City Hall going through the courts to challenge the proposed expansion.
Speaking to the BBC, Khan said: “When Heathrow comes out with their plans, as I’m sure they inevitably will, we will scrutinise them carefully.
"And we’ll have to hold the Government to task about them supporting a plan that doesn’t address the three concerns I’ve set out.”
He added: “We will use whatever means we can.”
During the Chancellor's growth speech in Oxfordshire, Reeves announced several infrastructure projects, including a regeneration of Manchester United's home ground Old Trafford and the reopening of Doncaster-Sheffield Airport.
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