London mayor opposes Heathrow third runway expansion

London Mayor Sir Sadiq Khan has formally opposed plans for a third runway at Heathrow Airport, arguing the expansion threatens environmental targets and transport networks. He submitted the objection in response to a government consultation. City Hall and Transport for London claim the expansion relies on outdated evidence and could add 22 million road journeys annually to the M4 and M25. They also estimate surface access costs of £9bn, with no funding agreement in place. Heathrow disputes the claims, calling expansion the UK's most important economic growth opportunity, citing 100,000 jobs and £150bn in trade. The government says it will consider all responses, with a final decision expected after a parliamentary vote in 2029.