President Biden announced plans Tuesday to double the funding the United States provides each year to help developing nations cope with the ravages of climate change and build greener economies.

Speaking at the United Nations, Biden framed the move as part of a broader return to multilateralism, saying the world must work together to combat daunting challenges such as the coronavirus pandemic, trade disputes and a rapidly warming planet.

Biden said he intends to work with Congress to boost the U.S. annual contribution to the problem to $11.4 billion, an amount he said is necessary “to support the countries and people that will be hit the hardest and that have the fewest resources to help them adapt.”

“This will make the United States a leader in public climate finance,” he said.

The new pledge aims to ease the distrust and anger among many small, developing nations who have done little to cause global warming but often have been hardest hit by its impacts. That rift has eroded the sense of unity that will be necessary at high-profile U.N. climate talks in Scotland in the fall, known as COP26, where world leaders face pressure to embrace a detailed global strategy to slow the Earth’s warming.

“Climate finance to help the world’s vulnerable people is the elephant in the room heading towards the COP26 climate summit,” Mohamed Adow, director of the African climate and energy think tank Power Shift Africa, said in a statement Tuesday. “It’s good to see President Biden is upping the amount that the U.S. is contributing, and others should certainly follow suit. However, the U.S. is still woefully short of what it owes.”

Developed countries pledged more than a decade ago to begin providing $100 billion annually by 2020 to help the most defenseless nations deal with the deepening consequences of sea-level rise, heat waves, intensifying hurricanes and other effects of warming — and to hasten the transition away from fossil fuels as those economies grow.

But that money has never fully materialized.

According to an updated analysis this month from the Organization for Economic Cooperation and Development, or OECD, developed nations mobilized $79.6 billion in 2019 to help poorer countries grapple with climate change — a 2 percent increase from the previous year, but still $20 billion short of what was promised. Less than three-quarters of that money funds greenhouse gas reductions, rather than addressing climate impacts, according to the United Nations.

“Failure to fulfill this pledge would be a major source of the erosion of trust between developed and developing countries,” U.N. Secretary General António Guterres told reporters Monday after a closed-door meeting on climate issues with dozens of world leaders. “Developed nations need to bridge this gap.”

Even as Biden has promised aggressive action to cut the nation’s emissions at least in half by the end of the decade, the United States has faced criticism for not paying its fair share to help more vulnerable countries battered by climate change.

In April, the Biden administration promised to double existing annual climate financing to developing countries by 2024, to $5.7 billion — a figure many critics said was too paltry given America’s role as the world’s largest historical carbon emitter. On Tuesday, Biden sought to double that number again, with a particular focus on funding to help nations adapt to calamities that already are unfolding.

In a statement Tuesday, Rachel Cleetus, policy director for the Union of Concerned Scientists, called the proposal “a welcome and much-needed sign that the United States is finally taking its global climate responsibilities seriously.” But she warned that the nation’s credibility on the world stage also depends on delivering on its promises to cut emissions at home — a goal that relies in part on significant funding under consideration in Congress.

Whether the latest climate finance figure represents a fair share for the United States, given its wealth and its role as the world’s largest historical emitter of greenhouse gases, is open to interpretation.

Earlier this year, an analysis by the independent international think tank Overseas Development Institute found the United States ideally should be contributing $31.9 billion to $49.4 billion a year toward climate help for developing nations. This week, a collection of advocacy groups, including the Natural Resources Defense Council and the Sierra Club, called on the administration to commit at least $12 billion per year by 2024.

While some climate activists praised Biden’s latest promise Tuesday, many also made clear they expect even bolder and broader commitments from the United States and other nations ahead of the key U.N. climate summit in November in Glasgow.

“In order to truly lead, the United States must genuinely do its fair share of climate action,” Brandon Wu, director of policy and campaigns for ActionAid USA, said in a statement Tuesday. “That means drastic domestic emissions reductions, and massively scaled up climate finance to enable reductions and support front line communities in poorer countries. What the administration has pledged to date fails to meet the scale of the challenge.”