The United Nations and Britain will co-host a global climate summit on December 12, the fifth anniversary of the landmark Paris Agreement, the world body said Wednesday.

"We have champions and solutions all around us, in every city, corporation and country," UN Secretary-General Antonio Guterres said.

"But the climate emergency is fully upon us, and we have no time to waste. The answer to our existential crisis is swift, decisive, scaled up action and solidarity among nations."

The world remains off-track to limit global temperature rise to 1.5 degrees Celsius by the end of the century, which scientists say is crucial to prevent runaway warming that would leave vast swathes of the planet inhospitable to life.

"In light of this urgency, Secretary-General Antonio Guterres and UK Prime Minister Boris Johnson will co-host a landmark global event convening global leaders... to rally much greater climate action and ambition," the statement said.

The two were to address the issue at a climate roundtable meeting hosted by Guterres on Thursday.

National governments will be invited to present more ambitious and high-quality climate plans at the summit, which would involve government leaders as well as the private sector and civil society.

Climate change has become an existential threat. It cuts across all of the UN's sustainable development goals (SDGs). 

On Tuesday, Chinese President Xi Jinping announced that the country aims to achieve carbon neutrality by 2060 in his speech via video link at the United Nations General Assembly (UNGA). The world reacted enthusiastically to the country's strong political will to lead a "green revolution."

The announcement came at a time when UN-advocated "Build Back Better" desperately and urgently demands leadership from leading economies to address the multiplicity of challenges created by climate change, the pandemic, social injustice and inequality. 

According to the UN, the December 12 summit is intended to increase momentum ahead of the United Nations Climate Change Conference (COP 26) to be held in Glasgow in November 2021.

(With input from AFP)