Joe Biden’s presidency is set to begin with the US rejoining the world’s climate accord, raising hopes of renewed momentum on tackling global warming.

Mr Biden’s promise to rejoin the Paris Agreement immediately is being widely welcomed – but is only the first step for the world’s second biggest polluter, with the global community keen to see what US climate action will follow.

And the UK Government is being urged to turn the new momentum the move will provide into action at home and on the international stage, in the run up to a UN summit that aims to drive efforts to curb dangerous warming of the planet.

The US formally left the Paris accord on the day after the presidential election in November, the only nation to do so in a move instigated by President Donald Trump, who pursued environmentally damaging policies while in office.

The deal commits countries to curb global warming to 2C above pre-industrial levels and aim for a more stringent 1.5C limit to avoid the worst climate impacts, which requires pollution to be cut to net-zero within a few decades.

The world remains well off track to meet those goals, and countries are expected to bring forward new, more ambitious climate plans ahead of the UN Cop26 summit being hosted by the UK in Glasgow in November.

Mr Biden has pledged to ensure the US reaches net-zero emissions by 2050, and as part of the return to the Paris Agreement, his administration must submit a new national action plan on how it will curb pollution this decade.

Countries such as China – which has pledged to become carbon neutral by 2060 but has not yet put forward its national plan – will be watching closely to see what action Mr Biden drives forward in the coming months.

During the election campaign, Mr Biden pledged 2 trillion dollars over four years as part of efforts to push towards 100% clean electricity by 2035, drive take up of zero-emissions vehicles and making buildings more efficient, as well as a diplomatic push on climate action.

The Paris Agreement is the world's most powerful tool for driving international climate action

With wins in two Senate races in the state of Georgia earlier this month, the Democrats now have a slim majority in the Senate which will make it easier to pass funding for climate action.

Alok Sharma, who is president of the Cop26 talks, said: “The Paris Agreement is the world’s most powerful tool for driving international climate action.

“So I am delighted that President Biden has stated his intent to put climate change at the top of his new agenda by rejoining and pledging that the US will commit to reaching net-zero.

“The responsibility to safeguard our planet for future generations rests with all of us. As hosts of Cop26, the UK will be working closely with the new US administration on this shared and pressing challenge.”

Shadow business secretary Ed Miliband welcomed the US returning to the global fight against climate change as a “cause for celebration and relief”.

That President-elect Biden is prioritising climate action on day one shows he recognises how incredibly high the stakes are,” he said, adding the new president was right to start with strong diplomatic action abroad and a green recovery at home.

He said the same could not be said of Boris Johnson, whom he accused of treating “climate change policy as window dressing rather than the building blocks of our country’s recovery”, and failing to deliver plans ambitious green economic recovery.

As the (Cop26) summit’s host, this Government needs to demonstrate to the world what needs to be done to help us avoid climate breakdown

“Boris Johnson has a long way to go if he wants to stand shoulder to shoulder with President-elect Biden and set the global agenda.

“Now is the time for statesmanship not showmanship, and real action not hot air.

“Having turned our back on the countries at the frontline of the climate emergency by cutting international aid, he must now dial up his diplomatic, strategic and political efforts to the maximum ahead of the vital Cop26,” he said.

John Sauven, executive director at Greenpeace UK, said Mr Biden’s move would breathe global momentum into the Paris deal, following more ambitious pledges last year by China, South Korea, the EU and Japan.

“The challenge for Boris Johnson is to capture that momentum and convert it into radical action ahead of this year’s climate meeting in Glasgow,” he said.

“This means rolling out much stronger measures to cut the UK’s emissions in areas like buildings, transport and power.

“As the summit’s host, this Government needs to demonstrate to the world what needs to be done to help us avoid climate breakdown.”