The UN’s climate chief on Thursday urged countries to unite against an ‘unprecedented threat’ to international cooperation from pro-fossil fuel forces — issuing the appeal as US president Donald Trump rattles the global order.

Simon Stiell, the head of the United Nations climate body, spoke in Istanbul as Turkey prepares to host the COP31 climate summit on its Mediterranean coast later this year, with Australia leading the negotiations.

‘COP31 in Antalya will take place in extraordinary times. We find ourselves in a new world disorder,’ Stiell said in an address alongside the Turkish president-designate of COP31, environment minister Murat Kurum.

‘This is a period of instability and insecurity. Of strong arms and trade wars. The very concept of international cooperation is under attack,’ he said.

Stiell made his plea as climate action is competing with concerns over security and economic growth around the world.

Trump has championed oil, gas and coal while moving to withdraw the United States from the UN’s bedrock climate treaty after pulling out of the Paris Agreement.

The US leader was poised Thursday to revoke a landmark scientific finding that underpins US regulations aimed at curbing planet-warming pollution.

The COP30 summit in Brazil late last year ended with a modest deal that lacked any explicit mention of fossil fuels amid opposition from oil giants like Saudi Arabia, coal producer India and others.

Stiell warned that international climate cooperation was ‘under unprecedented threat: from those determined to use their power to defy economic and scientific logic, and increase dependence on polluting coal, oil and gas’.

‘Those forces are undeniably strong. But they need not prevail. There is a clear alternative to this chaos and regression,’ he said. ‘And that is countries standing together.’