More than 165 world leaders have gathered at the UN headquarters to sign the Paris climate deal and get the ball rolling on plans to check global warming.

Held on Earth Day, Friday’s ceremony in New York City comes four months after the deal was clinched in Paris and marks the first step towards binding countries to the promises they made to cut greenhouse gas emissions.

French President Francois Hollande and Canada’s Justin Trudeau joined John Kerry, US secretary of state, for the ceremony attended by more than 165 governments, the largest single-day signing of an international agreement

While the US, China and India – the world’s top greenhouse gas emitters – will not be represented at their highest level, leaders of island states such as Fiji, Tuvalu and Kiribati, facing existential threats from rising sea levels, will formally present the already completed ratification by their parliaments.

Last month was the hottest March in modern history and 2016 is shaping up as a record-breaking year for rising global temperatures.

This year’s El Nino – dubbed Darth Nino – is believed to be behind droughts, floods, severe storms and other extreme weather patterns.

The Paris agreement will come into force as soon as 55 countries responsible for 55 percent of the world’s greenhouse gases have ratified the accord.

The target date for the agreement to begin is 2020.