JEREMY Corbyn's brother has slammed Greta Thunberg as an "ignorant brainwashed child" - just hours after the Labour leader met with the teenage climate activist.

Climate change denier Piers Corbyn described the trailblazing 16-year-old as "wrong" in a bizarre Tweet after she addressed MPs on the urgent need for action.

4 Jeremy Corbyn met with Greta Thunberg yesterday, describing the meeting as 'absolutely fascinating' Credit: Twitter

4 Climate change denier Piers Corbyn swiftly condemned internationally acclaimed Greta as ' wrong' in an derogatory Twitter post Credit: Matthew Chattle / Barcroft Media

4 Credit: Twitter

John Bercow welcomes climate change activist Greta Thunberg, 16, in the House of Commons

Addressing MPs at the House of Commons yesterday, she said: "This ongoing irresponsible behaviour will no doubt be remembered in history as one of the greatest failures of humankind."

Greta then sat down for a meeting with Corbyn as well as Caroline Lucas from the Green Party, Liberal Democrat leader Sir Vince Cable and the Westminster leaders of the Scottish National Party and Plaid Cymru, Ian Blackford and Liz Saville Roberts.

'I'M AN ACTUAL SCIENTIST'

Mr Corbyn afterwards described their encounter as "absolutely fascinating" and tweeted a smiling picture of him and Greta, describing young climate activists as "inspiring".

"We agreed that we would continue those discussions when we put forward policy so that we are measuring our policy against the environmental impact," he said.

"We have to have a much more focused and serious approach towards climate change and the damage we are doing to our natural world."

But his brother, who runs the website Weather Action, took a very different view.

I am an actual scientist of physics, meteorology, astrophysics and climate and say Greta Thunberg is wrong Piers Corbyn

Reposting a BBC News article titled "Teen tells UK politicians 'listen to climate scientists'", the 72-year-old Piers: "Listening to an ignorant brainwashed child is deranged."

He continued: "I am an actual scientist of physics, meteorology, astrophysics and climate and say Greta Thunberg is wrong and suffers mental abuse by manipulative adults."

Greta, who has been nominated for a Nobel Prize, began her movement with a lone protest outside Sweden’s parliament eight months ago.

On her visit to Parliament the climate crusader criticised the UK government for supporting shale gas fracking, greater exploitation of North Sea oil and gas fields and expanding airports.

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Miss Thunberg later said her future and those of her fellow children had been "sold".

She said: "We probably don't even have a future any more. That future has been sold so that a small number of people can make unimaginable amounts of money."

The teen also addressed civil disobedience group Extinction Rebellion on Saturday, telling eco warriors that "humanity is at a crossroads".

It was a pleasure welcoming UK youth climate strikers and @GretaThunberg to parliament. Young people will be the most affected by climate change - seeing them take charge of their future is inspiring. Labour's committed to working with young people campaigning to save our planet. pic.twitter.com/mBtQZqPUuv — Jeremy Corbyn (@jeremycorbyn) April 23, 2019

4 Greta Thunberg has become the most listened to voice on climate change since she took a stand in her native Sweden Credit: EPA

Climate change activist Greta Thunberg, 16, addresses EU Parliament in Strasbourg

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