The UK Government will provide an additional $2bn (£1.62bn) to the UN-backed Green Climate Fund (GCF), Prime Minister Rishi Sunak announced on Sunday at this year’s G20 summit in New Delhi, India.

The investment will be the UK’s largest single financial contribution to international climate change aid. The GCF, first established by 194 countries following the Copenhagen Accord at COP15 in 2009, is the biggest global fund dedicated to supporting developing nations in reducing their own emissions, as well as mitigating and adapting to the impacts of climate change.

The $2bn pledge represents a 12.7% increase in the UK’s previous contributions to the fund for the period 2020–23.

Sunak said at the summit: “The UK is stepping up and delivering on our climate commitments, both by decarbonising our own economy and supporting the world’s most vulnerable to deal with the impact of climate change.

“This is the kind of leadership that the world rightly expects from G20 countries. And this government will continue to lead by example in making the UK, and the world, more prosperous and secure,” he added.

At the summit, Sunak also said that he will resist “hair shirt” net-zero policies that aim to reduce carbon emissions, suggesting that he wants to limit the impacts of the energy transition on consumers.

“Net zero done in the right way can be very beneficial for jobs,” he said at the summit. “That is what we have got to make sure that the story is about. The net zero story for me should not be a hair shirt story of giving everything up and your bills going up. That is not the vision of net zero that I think is the right one for the UK.”

“Whole-of-society-approach” needed for net zero

Sunak’s approach goes against recommendations from UN climate change body the UN Framework Convention on Climate Change (UNFCCC). On Monday, the UNFCCC published its first global stocktake report on the progress of the Paris Agreement, finding that nations must now take a “whole-of-society-approach” to tackling climate change. To maintain global targets set out in the agreement, it recommends that member states implement “transformations across all sectors and contexts, including scaling up renewable energy while phasing out all unabated fossil fuels”.

Domestically, Sunak’s ambivalence towards the climate crisis has been the subject of an intensifying row within his own Conservative Party. Earlier this month, he faced a possible rebellion from Conservative Members of Parliament over the ongoing de facto ban on offshore wind in the UK. Sunak is now expected to loosen planning and permitting rules for onshore wind farms, an industry that has remained stagnant since 2015, as conflict continues to mount in the Commons.

Sunak also faced a serious backlash in July after he controversially announced plans to approve more than 100 new North Sea oil and gas licences. Environmental groups condemned the move as a “death sentence,” while a Scottish Greens climate and energy spokesperson called the decision “utterly reckless”, adding that it will leave a “long and destructive legacy”.

On Saturday, the Guardian reported that before announcing that he will not be attending the annual UN general assembly last month, Sunak was warned that he could face exclusion from key discussions on climate change because the UK’s climate policies are too unambitious. When he made the announcement, Sunak cited a busy schedule as the reason for not attending the summit, which is due to be held later this month. Multiple other world leaders including US President Joe Biden are expected to attend.

Ed Miliband, UK Shadow Net Zero Secretary, said on the possible exclusion: “If it is the case that Rishi Sunak has been excluded from global climate discussions, it will confirm what we in the UK already know – that he is a prime minister who is trashing the UK’s reputation of climate leadership, just like he has trashed our nation’s clean power resources.”