The world is "losing the race" against climate change, UN chief Antonio Guterres warned Thursday, demanding bolder action from governments to arrest runaway warming, reports AFP. Guterres delivered a no-holds-barred appraisal to business and political leaders gathered at the World Economic Forum in Davos, which has featured much hand-wringing on the planetary crisis this week.

"In my opinion it is the most important global systemic threat in relation to the global economy," the UN secretary-general told his high-calibre audience.

"Climate change is running faster than what we are," he said. "I believe we are losing the race."

The business community and civil society are increasingly engaged, "but the political will is still very slow", he said, lamenting the position of climate doubters.

"We are moving dramatically into a runaway climate change if we are not able to stop it."

A UN summit last month in Poland, which was designed to advance the Paris climate accord, laid bare continuing fissures over the share of responsibility among countries to cap temperature rises.

The Paris accord has been shaken by the withdrawal of the United States under President Donald Trump, and by threats to do the same by Brazil's new hard-right leader, Jair Bolsonaro.

Guterres, on an earlier Facebook Live broadcast, said the commitments made in Paris were already "not enough" but was "not hopeful" that nations would find the necessary resolve.

"If what we agreed in Paris would be materialised, the temperature would rise more than 3.0 degrees (Celsius)," he said.

"We need countries to make stronger commitments," Guterres said, calling for more measures to mitigate climate change and adapt to it, along with financial aid for poorer countries.