Boris Johnson is being asked by the London Assembly to drop his plans for a new airport in the Thames Estuary which could replace Heathrow.

The Assembly has warned that the idea would be disastrous for London’s economy, with up to 100,000 jobs at risk should Heathrow be forced to close.

It would also increase noise, congestion and pollution for millions of people across east and south east London as well as create environmental damage to estuary wildlife, they fear.

“The Mayor must drop this ridiculous vanity project,” said Assembly member Murad Qureshi.

“Such an airport would have a devastating effect on the economy as well as a legacy of noise, congestion and pollution for millions of people in Havering, Barking, Bexley and Bromley.”

The Assembly passed a resolution earlier this month saying the Mayor’s plans are “simplistic and ill-considered” and called on him to abandon them.

Heathrow would need to close for a new Estuary airport to succeed, it pointed out, which would cost 100,000 jobs.