US climate envoy John Kerry will embark on a visit to Japan and China Tuesday as Washington tries to build momentum ahead of a key summit on combatting global warming set for November.

Kerry, who already visited China in April, will go to Tianjin to "continue discussions on key aspects of the climate crisis," the State Department said in a statement on Monday.

During the trip that is due to end on Friday, the former secretary of state will also meet international counterparts in Tokyo, the statement added, to "discuss efforts to drive collective climate action".

The US envoy's Asian tour "bolsters the United States' bilateral and multilateral efforts to raise climate ambition" ahead of the COP26 climate summit, to be held in Glasgow, Scotland, in November.

After Kerry's visit to Shanghai in mid-April, the two countries pledged to "cooperate… to face the climate crisis," according to a joint statement, but Beijing said at the end of July that this cooperation would depend on "the overall health" of bilateral relations.

The UN's Intergovernmental Panel on Climate Change report, published in August, warned the world is on course to reach 1.5 degrees Celsius of warming by around 2030, a decade earlier than predicted just three years ago.

Years in the making, the sobering report approved by 195 nations shines a harsh spotlight on governments dithering in the face of mounting evidence that climate change is an existential threat.

UK police warn climate protesters after landmark bridge blocked
London (AFP) Aug 30, 2021 –

Police in London on Monday warned activists from Extinction Rebellion they faced arrest after the environmental pressure group blockaded Tower Bridge, one of the capital's most recognisable landmarks, to traffic.

The Metropolitan Police said demonstrators, who are halfway through two weeks of promised protests in the British capital, had used a van and a caravan to obstruct the world famous crossing.

"Officers were on scene almost immediately," the force said on Twitter.

"We are working with @CityPolice to get traffic moving again," it added, referring to the neighbouring City of London police department responsible for the heart of the financial district.

"We'll be warning those protesting that this obstruction of roads is unreasonable and they must disperse. If they do not move, they may be arrested," the Met said in a later update.

Extinction Rebellion kicked off a new round of disruptive protests last Monday, with thousands of climate change activists since thronging central London to demonstrate against perceived global inaction on the issue.

"Another Towering achievement from #ExtinctionRebellion as the world's most famous bridge is BLOCKED," the group's UK arm tweeted Monday.

On Friday, hundreds protested in the City of London financial hub against the funding of fossil fuel industries by lenders in the so-called Square Mile, as part of the ongoing action dubbed the Impossible Rebellion.

Police have arrested dozens over the past week, including 34 during rallies on Sunday.