The landmark Paris agreement on climate change moved closer to reality Wednesday after 31 countries joined during the United Nations General Assembly.
UN Secretary-General Ban Ki-moon voiced confidence that the accord, through which countries commit to take action to stem the planet's rising temperatures, would come into force by the end of the year.
"The momentum is remarkable," said the outgoing UN chief, who convened a meeting on the Paris accord during the annual UN gathering of leaders.
"When the Paris agreement enters into force this year, it will be a major step forward on our journey for a more secure, more equitable and more prosperous future," Ban said.
The accord requires all countries to devise plans to achieve the goal of keeping the rise of temperatures within two degrees Celsius (3.6 Fahrenheit) above pre-industrial levels.
Scientists say that such a temperature rise still poses risks but could save the planet from the worst effects of climate change, including worsening flooding, storms and droughts that may cause food shortages, species extinction and significant human displacement.
The countries that joined the accord on Wednesday included Latin American powerhouses Argentina, Brazil and Mexico as well as major fossil fuel powers Brunei and the United Arab Emirates.
To come into force, the Paris agreement needs ratification from 55 countries that account for at least 55 percent of the planet's greenhouse gas emissions responsible for climate change.
With Wednesday's event, in which leaders ceremonially submitted paperwork to ratify the accord, a total of 60 countries have joined the Paris accord, meeting the threshold.
But they account for just less than 48 percent of emissions, according to UN figures.
Ban's office said that 14 other countries accounting for 12.58 percent of emissions had signaled they would ratify the accord this year, meaning the agreement is virtually certain to come into force, barring a widespread change of heart.
Notably, the European Parliament is expected to vote to approve the Paris accord next month.
China and the United States, the two largest emitters, gave a major boost to the accord when they signed on during a summit earlier this month between Presidents Xi Jinping and Barack Obama.
French Environment Minister Segolene Royal, who heads the body behind the Paris accord, told AFP earlier in the week that she hoped it would come into force before the next UN climate meeting on November 7 in Marrakesh, Morocco.
That conference opens one day before the presidential election in the United States, in which Republican candidate Donald Trump has dismissed mainstream science on climate change and vowed to tear up the Paris accord if elected.
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