Jeremy Corbyn would take Donald Trump to task on the environment if he was the Prime Minister at the G20 summit, he said.
The Labour leader said he would also challenge the US President on the “economic orthodoxy” of austerity, which he said was creating inequality around the world, if he were in Theresa May’s place in Hamburg.
Corbyn was speaking in the North East of England where he addressed a large crowd at the Durham Miners’ Gala, which he said was “Europe’s biggest demonstration of working class culture”.
Organisers said 200,000 people were at the Old Racecourse for the traditional ‘Big Meeting’ of brass bands and pit banners, which culminates in political speeches.
Asked what he would be doing if he was Prime Minister at G20, he said: “I would be very strongly challenging Donald Trump on his wish to walk away from the Paris Climate Change accords.
“They are crucial for the future of all of us and I hope he will understand that unless all the nations of the world get together to reduce emissions and try to preserve and protect our planet then the next generation are going to have more climate disasters, more extreme weather conditions and there’s going to be more environmental refugees around the world.
“I think these are serious times and it requires serious attention to them.”
Trump met May at the summit and the President later said he expects a trade deal with the UK to be completed “very, very quickly”.
Other G20 leaders left Trump isolated by signing a deal which said the Paris accord was “irreversible”.
After the meeting, May said: “I did bring the issue of climate change agreement up with President Trump.
“I have had a number of conversations with him while I’ve been here at the G20. What I did was encourage him to bring the United States back into the Paris Agreement, and I continue to hope that’s what the United States will do.”
Corbyn, who watched some of the parade from the County Hotel balcony, praised the traditional Gala, which organisers said was the biggest since the 1960s.
He said: “It’s incredibly important for everyone to be here today.
“It is the most amazing demonstration of community strength.
“It’s grown out of the struggles of the miners during the 19th, 20th and now in this century, it’s a community event.”
He refused to be drawn into a row about some local Labour MPs being “disinvited” from the event.
From the gala platform, he claimed to be leading a “government-in-waiting” which could end austerity and scrap the cap on public sector pay rises.
Armed police on visible patrol and more roads were closed than usual as organisers beefed up security in the wake of a string of attacks.
Corbyn was interrupted by a woman during his speech.
Just as he invited May to step down and call a general election, there was a disturbance.
People booed as the woman appeared to be pleading with Corbyn to speak to her and he said he would talk to her after he finished his address.
There were chants of “Ooh Jeremy Corbyn” from the crowd throughout the afternoon and he was cheered loudly when he finished, holding his arms aloft.