Jeremy Clarkson has told Greta Thunberg to 'shut up and go back to school' in an excoriating attack on the teenage environmental activist.

The outspoken broadcaster, 59, hit out at the Swedish campaigner who he dubbed 'mad and dangerous', the latest in a series of attacks against the 16-year-old.

Clarkson, who was fired from the BBC in 2015 after rowing with a Top Gear producer over a steak, was a long time critic of global warming science but recently admitted he'd had a change of heart after filming in southeast Asia.

The television presenter, who was in Australia promoting the latest season of The Grand Tour, doubled down on his criticisms of the climate change campaigner.

'She's mad and she's dangerous and she's causing young children sleepless nights with her idiocy,' he said. 'I think she needs to go back to school and shut up.'

The outspoken broadcaster, 59, hit out at the Swedish eco-warrior who he dubbed 'mad and dangerous', the latest in a series of attacks against the 16-year-old

Clarkson's comments come just days after slammed Ms Thunberg in an interview with The Independent in which he branded her a 'stupid idiot.'

He said her speech at the United Nations - where she accused leaders of stealing her 'dreams and childhood' - offered no solutions.

'I think she's a weird Swede with a bad temper. Nothing will be achieved by sailing across the ocean in a diesel-powered yacht, and then lying about the diesel engine, he told the publication.

He added that we've been aware of climate change for quite some time, and now 'there's that weird Swede running around making all sorts of 'we're going to die' noises, so we're all aware of it.'

'But rather than having her jumping up and down and waving her arms in the air, you can actually go there and say, 'Bloody hell, fire! Look at what this climate change has done to this place.

'We simply said, 'Here's an example of it.' What do you want me to do now? Get on my carbon fibre yacht and go and shout at Donald Trump?'

Clarkson, who was fired from the BBC in 2015 after rowing with a Top Gear producer over a steak, was a long time critic of global warming science but recently admitted he'd had a change of heart after filming in southeast Asia

Thunberg sat next to a placard reading 'school strike for climate' on the sidelines of the World Economic Forum

He continued, criticising her for going to Chile for the climate change conference which was then moved to Madrid, saying that it made him 's*** himself laughing'.

Clarkson's latest broadside came during an interview in which he discussed how he saw the impact of climate while filming The Grand Tour in Cambodia.

'I don't think I've ever actually seen the effects of global warming. When you see those houses on stilts on the show - 40 to 50 feet - and the water is miles away,' he said.

'And then you think, 'the water's supposed to be up there this time of year and it's down there.' It's unbelievable.

'So that's a remarkable thing and I know there'll be a load of kids saying, 'ha! You see. There you are!' That's fine. Now go to school. Learn science and do something about it.'

Last month Clarkson admitted he 'didn't have a clue' about climate change after the Cambodia trip.

On Tuesday Greta arrived in Portugal after a three-week voyage across the Atlantic Ocean, telling cheering supporters the journey had 'energised' her in the fight against climate change.

Ms Thunberg rose to fame after giving an impassioned speech at the United Nations this year

The Swedish teenager, whose solo protests outside the Swedish parliament helped galvanize youth support, sailed into Lisbon on a voyage from the US to attend this year's UN climate conference.

She has refused to fly because of the amount of greenhouse gas emitted by planes, a stance that put her planned appearance at the meeting in doubt when the venue was moved from Chile to Spain a month ago.

Speaking at the United Nations earlier this year, blasted international delegates for not taking responsibility for fixing the planet's warming climate.

'I shouldn't be up here. I should be back in school on the other side of the ocean. Yet you all come to us for hope. How dare you.

'You have stolen my dreams and my childhood with your empty words,' she said in her speech at the Climate Action Summit 2019 in New York.

Greta Thunberg arrives in Lisbon on a boat as she finishes her voyage across the Atlantic Ocean

In 2009, environmental campaigners dumped manure on Mr Clarkson's front lawn in protest against his attitude on global warming.

Eco-campaigners said he has a 'blase attitude to climate change' because of his love of high-powered cars and 4x4 cars.

Activists from environmental group Climate Rush unloaded two bag-loads of horse manure at his home with a banner which read: 'This is what you're landing us in'.

The seven female protesters, dressed as suffragettes, made the stop outside Clarkson's home as part of their month-long horse-and-cart road show around the south west of England to raise awareness of climate issues.