Last modified on Wed 5 May 2021 04.18 EDT Young people concerned about the climate crisis and air pollution are urging the London mayor, Sadiq Khan, to abandon his plans for a new four-lane road tunnel under the Thames or risk losing their support. Climate justice campaigners, anti-pollution activists and key youth groups inside the Labour party say Khan, who is standing for re-election on Thursday, is ignoring climate scientists, economists and health experts by pressing ahead with the £2bn Silvertown tunnel scheme in east London. They warn that unless he cancels the plans he, and the Labour party, could lose the backing of a generation of young voters.