The US will provide $1 billion to the UN's flagship climate fund - the first such contribution in six years. Joe Biden made the pledge as he hosted a virtual meeting of world leaders on Thursday to galvanize high-level leadership to limit global warming to 1.5°C. It is the first time since 2017 that the U.S. has pledged cash to the Green Climate Fund (GCF), which supports developing countries in reducing emissions and adapting to climate impacts. The move was part of a broader call for action by the Major Economies Forum on Energy and Climate, a group of more than 20 high-emitting developed and developing countries that produce about 80 % of global greenhouse gases.