Sir Keir Starmer pledged to “restore the UK’s role as a climate leader” as he launched an international green alliance at the G20.
Countries including Brazil, Australia, Canada and France are among those to have signed up to the first “mission” of the UK-led Global Clean Power Alliance, on the last day of the summit in Rio de Janeiro.
It comes on the final day of the summit of world leaders, that has coincided with the 1,000th day of the conflict in Ukraine.
Earlier on Tuesday, Downing Street described the leaders’ statement as “disappointing” on its stance over the war.
Last year’s document called for the cessation of military destruction or other attacks” on infrastructure related to food and energy and also noted concerns about the security of civilians.
Russia is a member of the G20, and minister of foreign affairs Sergei Lavrov has been at this week’s summit in Rio de Janeiro.
Asked about the statement on Tuesday, a Downing Street spokeswoman said: “It is disappointing. It is not unexpected, given the G20 obviously brings together a range of countries who have differing views.
“Not least, it includes representatives of the Russian government in attendance.”
Tuesday saw the PM hold a bilateral meeting with host, Brazilian President Lula da Silva, as well as a trilateral with Prime Minister of Italy Giorgia Meloni and the Prime Minister of Japan Shigeru Ishiba.
The three leaders discussed their joint fighter jet programme and it was confirmed that the HQ for the project is due to be based in the UK.
He had said in a statement that he wanted “our clean energy ambitions to go global” and promised to “restore the UK’s role as a climate leader on the world stage”.
According to Downing Street, the signatories will share expertise with the goal of tripling renewable energy and doubling energy efficiency, and the group will be driven by “missions”.
The first mission will relate to finance and will look towards private finance to ensure developing countries are able to keep up on the green transition.
The countries and organisations signed up are the African Union, Australia, Barbados, Brazil, Canada, Chile, Colombia, France, Germany, Morocco, Norway, Tanzania, and the United Kingdom.
The US and EU will also partner with the UK on the scheme.
There was no mention of the China and India, who are among the largest polluters.
At a signing ceremony to mark the alliance, Sir Keir described finance as the “biggest challenge” on climate.
“This is about harnessing the political leadership, needed to unlock investment on a huge scale, so that no developing country is left behind,” he added.
