UN Secretary-General Antonio Guterres told countries gathered at the start of the Cop27 summit in Egypt on Monday they face a stark choice: work together now to cut emissions or condemn future generations to climate catastrophe.

The speech set an urgent tone as governments sit down for two weeks of talks on how to avert the worst of climate change, even as they are distracted by Russia’s war in Ukraine, rampant consumer inflation and energy shortages.

“Humanity has a choice: cooperate or perish,” Guterres told delegates gathered in the seaside resort town of Sharm el-Sheikh. He called for a pact between the world’s richest and poorest countries to accelerate the transition from fossil fuels and the delivery of funding to ensure poorer countries can reduce emissions and cope with the impacts of warming that have already occurred.

“The two largest economies — the US and China — have a particular responsibility to join efforts to make this pact a reality,” he said. Guterres asked countries to agree to phase out the use of coal, one of the most carbon-intense fuels, by 2040 globally, with members of the Organisation for Economic Cooperation and Development hitting that mark by 2030. “Greenhouse gas emissions keep growing. Global temperatures keep rising. And our planet is fast approaching tipping points that will make climate chaos irreversible,” he said.

“We are on a highway to climate hell with our foot on the accelerator.” Immediately after Guterres’ speech, UAE President Sheikh Mohammed bin Zayed al-Nahya took the stage and said his country, an Opec member, would continue to produce fossil fuels for as long as there is a need. “The UAE is considered a responsible supplier of energy,” he said.