German Chancellor Angela Merkel said Saturday that the G20 would sign a similar deal on climate change to that agreed at the last meeting in Argentina, where the United States was isolated.

"We will have a similar text to Argentina. A 19+1 declaration," Merkel told reporters on the sidelines of a G20 meeting in Osaka.

At the G20 meeting in Buenos Aires in December 2018, leaders whose countries had signed up to the Paris agreement seeking to limit climate change declared the accord "irreversible" and committed to its "full implementation".

However, the United States at the time said it "reiterates its decision to withdraw from the Paris Agreement" and "affirms its strong commitment to economic growth and energy access and security".

Climate activists form human chain around German parliament
Berlin (AFP) June 28, 2019 –

Demonstrators formed a human chain to symbolically lock politicians in the German parliament building in Berlin Friday, as calls by schoolchildren for climate action continued into the capital's summer holiday.

The group stretched a bolt of red cloth from hand to hand while holding signs with messages like "2038 is too late" — a reference to the government's planned date for ending electricity generation from coal.

"While the politicians are serving their final minutes before the summer holiday, we're outside saying: People who make no climate policy don't deserve a break!" the "Fridays for Future" movement tweeted.

"That's why we're forming a human chain and demanding that you continue sitting" in the chamber, the account added.

Launched by Swedish activist Greta Thunberg, "Fridays for Future" has seen pupils "strike" against school teaching each Friday for months across Europe.

Around 500 people joined a march to the Reichstag parliament building from the Invalidenpark square, close to the city's Natural History Museum which opens its doors to the activists in weekly discussion forums.

Friday's protest comes one week after tens of thousands of young people from around Europe rallied in the western city of Aachen to demand faster reduction of greenhouse gas emissions, in the movement's biggest German demonstration yet.

Some of those demonstrators later joined the "Ende Gelaende" civil disobedience action in which activists blockaded a massive open-cast brown coal mine.

Climate change has become a top public concern in Germany, with the Greens party shooting up to poll neck-and-neck with Chancellor Angela Merkel's conservatives for the first time in recent weeks.