New Thames tunnel will make London pollution worse, warn climate activists

Campaigners say Sadiq Khan's support for a four-lane road under the river is at odds with his environmental aims

Burrowing deep under the Thames, Silvertown tunnel is scheduled as the first new road link across the capital's river for 30 years. But, the four-lane highway, due to be completed in 2025, is about to become the focus of environmental protests in the lead-up to the Cop26 global climate summit in Glasgow in November.

Preliminary construction work has begun and tunnelling is due to begin next spring, but campaigners insist it is not too late to halt the 1bn-plus engineering project and are planning protests at both ends of the tunnel later this month.