London mayor Sadiq Khan is warning that time is running out to act on the climate emergency, which will have devastating effects on the city - and could see Tower Hamlets and Newham under water.

Vulnerability mapping has shown the two boroughs are among six London areas at particularly high risk of flooding and overheating, along with Islington, Hackney, Hammersmith and Fulham, and Brent.

In a speech on September 23, ahead of UN climate talks at Cop26 in Glasgow, Mr Khan warned the climate emergency remains one of the biggest threats the world faces.

He said the capital is at a crossroads as he launches a campaign to raise awareness of the crisis and engage Londoners, with changes such as the ultra low emission zone (ULEZ) expansion to curb traffic pollution and a new Environment Bill is set to go through Parliament.

The analysis suggests rising temperatures could make the Tube potentially unbearably hot for more than a month a year.

A quarter of London’s rail stations are now at high risk of flooding, and this summer parts of the city were hit by flash floods.

City Hall's study also shows one in five schools, and nearly half of London’s hospitals, are at risk of flooding, and 200,000 homes and workplaces are at medium or high risk of surface water damage.

Furthermore, on the basis of new World Health Organisation (WHO) guidelines for limits on air pollution issued on September 22, all school children in London attend their classrooms surrounded by toxic air, officials said.

In his speech at the Barbican Centre, Mr Khan said: “We either take bold action now or face the consequences – with catastrophic impacts on our environment, the air we breathe and the climate.

“I’m determined for London to be a world leader in tackling the twin dangers of air pollution and the climate emergency so that we can deliver a brighter future for London – one that’s greener, fairer and more prosperous for everyone.”

Mr Khan has committed to making London a zero-carbon city by 2030, and expanding the ULEZ.

“But I can’t do it all alone," he said. "That’s why today I’m launching my city-wide campaign to inspire all Londoners – individuals, businesses and communities – to take action."