China's President Xi Jinping will attend US President Joe Biden's virtual climate summit this week, Beijing said Wednesday, as the world's top polluting nations seek rare common ground despite wider political tensions.

Biden has invited 40 world leaders including Xi and Russia's Vladimir Putin to the meet starting on Earth Day, meant to mark Washington's return to the front lines of the fight against climate change after former president Donald Trump disengaged from the process.

The virtual summit will be the first meeting between the two leaders since Biden became president.

Xi will give an "important speech" at the meeting, said the Chinese foreign ministry, days after a trip to Shanghai by US climate envoy John Kerry -- the first official from Biden's administration to visit China.

Kerry and Chinese counterpart Xie Zhenhua had said they were "committed to cooperating" on tackling the climate crisis, even as sky-high tensions remain on multiple other fronts.

Washington and Beijing's pledge to cooperate comes amid acrimony over accusations about China's policies in Hong Kong and its treatment of Uyghurs in its northwestern Xinjiang region -- criticisms Beijing rejects as interference in its domestic affairs.

No global solution on climate change is likely without both the US and China on board, since the world's top two economies together account for nearly half of the world's total greenhouse gas emissions.

No global solution on climate change is likely without both the US and China - which account for nearly half of the world's total greenhouse gas emissions - on board
No global solution on climate change is likely without both the US and China - which account for nearly half of the world's total greenhouse gas emissions - on board AFP / Fred DUFOUR

Biden has made climate a top priority, turning the page from his predecessor Donald Trump, who was closely aligned with the fossil fuel industry.

The US president has rejoined the 2015 Paris accord, which Kerry negotiated as secretary of state and which committed nations to take action to keep temperature rises at no more than two degrees Celsius (3.6 Fahrenheit) above pre-industrial levels.

China -- the world's top carbon emitter -- has vowed to reach peak emissions by 2030 and become carbon neutral thirty years later.

Meanwhile Biden is expected this week to announce new US targets on reducing carbon emissions as part of the summit amid mounting global alarm over record-breaking temperatures and increasingly frequent natural disasters.

Beijing has said the US needs to take more responsibility on climate change, with foreign ministry spokeswoman Hua Chunying calling Washington's return to the Paris accord "a truant getting back to class".

Xi joined another virtual climate summit with France and Germany last week, where he said developed countries should "set an example" in reducing emissions and support developing nations' responses to climate change, state news agency Xinhua reported.