Oslo: Global warming is on course to exceed the most stringent goal set in the Paris Agreement by about 2040, threatening economic growth, according to a draft report that is the UN's starkest warning yet of the risks of climate change.

Global warming is melting the habitat of polar bears, which cannot survive without sea ice, using it to raise their young, to travel and as a platform for hunting seals - their primary food source. Credit:AP

Governments can still cap temperatures below the strict 1.5-degree Celsius ceiling agreed in 2015 only with "rapid and far-reaching" transitions in the world economy, the UN's Intergovernmental Panel on Climate Change (IPCC) says.

The final government draft, dated June 4 and obtained by Reuters, is due for publication in South Korea in October after revisions and approval by governments.

It will be the main scientific guide for combating climate change.