The US decision to withdraw from the Paris climate agreement has given a "global push" to the deal, as other signatories have strongly recommitted to the landmark accord, UN chief Antonio Guterres said Monday.

President Donald Trump, whose country is the world's second biggest producer of greenhouse gases after China, drew widespread criticism when he announced on June 1 that he would quit the 2015 pact.

"Since the decision by the US government to abandon the Paris accords, we have been witnessing a global push and a reaffirmation by all the other governments of their commitment" on climate change, Guterres told a conference in Lisbon.

"It's obvious for the European Union, China and India," he added.

Guterres recalled that he had recently met the leaders of China and India, describing them as countries which were "crucial" for the success of the Paris accords.

"Their commitment is clear," he said.

"In the United States, this push is generating at the level of cities, in some states and in the business world a very strong commitment towards the green economy," the UN chief said.

Former New York mayor Michael Bloomberg, who has become a UN special envoy for cities and climate, "is convinced that the United States will be able to reach the targets it set itself under the Paris accord," said Guterres.

The Paris agreement, struck in the French capital in December 2015, aims to keep the increase in average world temperatures to "well below" two degrees Celsius (3.6 degrees Fahrenheit) above pre-industrial levels.