Sadiq Khan has thrown his weight behind a campaign to stop a controversial “toxic” incinerator being built next to a nature reserve in Belvedere.

The Mayor of London has urged the government to pull the plug on Cory Riverside Energy’s proposed waste incinerator at their site near to Crossness Nature Reserve.

Local councillors and wildlife enthusiasts have long criticised the proposals claiming they will be detrimental to the rare wildlife and precious green open space.

The Mayor has now chimed in, writing to the secretary of state as he considers the plans put forward by Cory, which already has one plant in Belvedere.

Mayor Khan joined criticism that burning waste has a negative impact on London’s air quality.

He said: “London’s air is a toxic air health crisis and the last thing we need, in our modern green global city is another harmful waste-burning incinerator polluting our city.

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“Emissions from incinerators are bad for our health, bad for our environment and bad for our planet.

“Instead of granting permission for an unnecessary new incinerator that will raise pollution levels in the boroughs of Bexley and Havering, the Government should focus on boosting recycling rates, reducing the scourge of plastic waste and tackling our lethal air.

“I am urging ministers to reject this proposal.“

According to a statement from the mayor’s office, Mr Khan sent a report to business secretary Greg Clark outlining his opposition to the plans.

Environmental campaigners using the acres of greenbelt land say adding another huge incinerator will drive the rare wildlife across the river, ruining a “hidden jewel” and one of London’s few nature reserves.

Wildlife fans can see rare bats and birds which flock to the green space on the banks of the Thames, which last year was greeted by an extremely rare sighting of the Penduline Tit.

Campaigners say adding another plant, which would be even closer to Cory’s boundary on the site, would drive birds like the red kite, buzzard, marsh harrier or barn owl away from the habitat.

MORE MP launches petition to stop Riverside Energy Park in Belvedere

Cory says it will provide up to 30 megawatts of ‘affordable energy’ to houses in the area, and offer up to 6,000 jobs on the new site during construction and a further 100 once it is up and running.

Cory’s incinerator takes waste from across London, not just Bexley, and burns it at high temperatures to generate energy.

Responding to the Mayor’s stance, Dougie Sutherland, CEO of Cory Riverside Energy, said: “Everyone in London wants a clean city and it’s easy to assume that incinerating waste is an outdated method. But, done responsibly, it’s a modern, clean and efficient solution that does not impact on London’s recycling rates.

“The Mayor is simply wrong to say that the proposed plant would emit more than four times as much NOx as our existing facility and the Crossness sewage plant combined. In fact, levels will be only one third of current emissions from the existing Cory facility, which has operated consistently within all environmental limits since day one.

“We want to reassure all Londoners that this would be the most modern and cleanest energy from waste plant in the UK.”

MPs Teresa Pearce and Sir David Evennett have objected to the application, which is set to be decided by spring next year .