More than 20 nations including the United States called for a tripling of nuclear energy to drive down emissions on Saturday as world leaders assembled for a second day at UN climate talks in Dubai, Ednews reports citing Yahoo News.

With smoggy skies in Dubai highlighting the challenges facing the world, other pledges are expected at the COP28 conference, including stepping up the deployment of renewable energy and cutting methane emissions.

The use of nuclear power as a cleaner alternative to fossil fuels is highly controversial as environmental groups are concerned about safety and the disposal of nuclear waste.

But more than 20 nations ranging from the US to Ghana, Japan and several European countries said in a declaration that it plays a "key role" in the global goal of achieving carbon neutrality by mid-century.

They called for the tripling of nuclear energy capacity by 2050 from 2020 levels.

"We are not making the argument to anybody that this is absolutely going to be a sweeping alternative to every other energy source," US climate envoy John Kerry said at the COP28 conference in Dubai.