The US and China have shunned the UK’s flagship coal pact, dealing a severe blow to the COP26 climate summit and drawing a warning from the world’s leading energy body, which said the chances of limiting global warming to the goals of the Paris accord were “close to zero”.

Fatih Birol, head of the International Energy Agency, said a deal to phase out the use of the dirtiest fossil fuel was one of three actions that must emerge from the Glasgow meeting for the rise in temperatures to stay below 1.5C since preindustrial times.

Global temperatures have risen an estimated 1.1C in that period.

“Without addressing this problem, the chances to reach our 1.5C target is close to zero,” Birol told the Financial Times. “I hope all the countries are going to be part of a deal where they can take these early steps for early retirements or repurposing their coal plants,” he added.

The UK hosts wanted the summit to be known for consigning “coal to history”, but were forced to weaken the pact to draw more signatories. The timeframe was extended to allow another decade, or even longer, for coal plant shutdowns.

After frantic last-minute negotiations, 40 countries including South Korea, Vietnam, and Poland signed the pledge, which commits them to shut their coal plants and stop issuing licenses for new plants.

A further six countries including Indonesia and Morocco signed up to portions of the deal, without endorsing the entire pact. The world’s top-three coal consumers in China, India, and US, representing 72 percent of global emissions from coal-fired power, did not sign, nor did Australia.

“Phasing out coal in China and India even over the next two decades is simply not feasible due to their reliance on coal to meet demand,” said Dan Klein, head of Future Energy Pathways, S&P Global Platts.

The US said it was still committed to a “clean energy future” and is preparing to end financing for fossil fuels overseas. The Biden administration has its hands tied as it tries to win the support of Senator Joe Manchin for its critical infrastructure plan. Manchin is a Democrat who represents coal-producing West Virginia.