A mayoral candidate has pledged to do whatever she can to stop the Viridor incinerator despite work on the controversial project beginning in the summer.

Green candidate Sian Berry visited the Beddington site of the proposed £1 billion incinerator today, along with Green parliamentary candidate for Croydon North since 2010 Shasha Khan.

Ms Berry said: “Incineration harms both human health and the environment and the Mayor’s own policies acknowledge it’s the worst form of waste management.

“It also acts as a disincentive to recycling, not least because giant plants like this one will need to import waste to fulfil its long-term contracts and make profits for its shareholders over 25 years.

“If the facilities were provided London could reduce, re-use or recycle all its waste.

“That would save more energy than we could produce from burning it.

“If we are serious about making London the greenest city in the world, we need to embrace these 21st century approaches not the toxic, last-century idea of incineration.”

A spokesman from Sutton Council said: “The Mayor has set a target for no waste to landfill by 2031 and has given permission for the energy recovery facility in Beddington.

“He has also said that energy should be generated from rubbish that cannot be reused or recycled.

“The network will help the Mayor to achieve his target of 25 per cent of London’s energy supply coming from decentralised energy resources by 2025.”

Viridor was granted planning permission in 2014 to build the incinerator.

Mr Khan famously took Sutton Council to a judicial review in the hope of getting the decision to grant planning permission for the energy recovery facility in Beddington Lane overturned.

He lost his bid in April this year.

It will deal with up to 302,000 tonnes of non-recyclable waste from Merton, Croydon, Sutton and Kingston councils.

Last month Sutton Council launched the Sutton Decentralised Energy Network (SDEN) which will use heat from the incinerator to provide low-carbon energy.

The authority claimed it would provide energy for up to 19,000 homes.

Negotiations are underway with Barratt Homes, the developer of 725 new homes on the Felnex site, to sign new home owners up to the network.

The authority said the scheme will prevent more than 5,000 tonnes of carbon dioxide being released into the atmosphere.