Friends of the Earth said the Thames Estuary airport scheme was a "pie-in-the-sky plan" and that Mr Johnson should "stop pitching communities in west London against those in Essex and Kent and back transport solutions that don't wreck our planet".
Rodney Chambers, leader of Medway Council in Kent, said: "For five years now, Boris has failed to listen to the huge number of people who have said that placing an airport in North Kent, on or near the Thames Estuary, is a complete non-starter."
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