Donald Trump isn’t at the global climate summit in Brazil. But he was on the minds of some of his fellow world leaders Thursday, who used their time on stage to try to isolate the U.S. president and his hard-line opposition to their agenda.

In speeches meant to highlight their support for efforts to halt rising temperatures, a few of the heads of state at the COP30 climate talks in the Amazonian port city of Belém could not resist the chance to admonish the U.S. president directly.

“Mr. Trump is against humankind,” said Colombian President Gustavo Petro, who pointed to the American president’s absence from the gathering and called for an economy free of oil and natural gas.

Gabriel Boric, Chile’s president, took Trump to task for a September speech to the U.N. General Assembly in which the U.S. leader denounced the notion of human-caused climate change as a “con job” and a “hoax made up by people with evil intentions.”

“That is a lie,” Boric said, emphasizing the importance of science and facts. “We might have legitimate discussions about how to face these things, but we cannot deny them.”

The White House did not immediately respond to a request for comment.

Brazilian President Luiz Inácio Lula da Silva, whose country is hosting the two-week summit, did not name Trump but hit out at “extremist forces that fabricate fake news on climate for political gain.”

He urged countries gathering at the conference to develop a road map to “overcome fossil fuels.”

Since returning to office in January, Trump has championed coal, oil and gas and sought to squash clean energy efforts in the U.S. and abroad. He has removed the U.S. from the 2015 Paris climate change agreement, for the second time, and has used the threat of tariffs to try to bolster sales of American fossil fuels.

The speeches from a handful of leaders displayed, at times, the anger and dismay that countries feel about the U.S. breaking its promises and attempting to undermine the global effort to tackle global warming. Other leaders tried to brush off the American absence as simply an act of economic self-harm.

But the tough talk could not hide the ambivalence that many countries beyond the U.S. have toward this year’s U.N. climate talks.

Just a small number of European leaders turned up, while some other countries have sent ministerial representatives. Canada’s Mark Carney, a former U.N. climate representative, stayed home. The European Union’s 27 member countries could not agree on a climate goal to present at the conference until Wednesday morning — and only after watering down existing pollution-cutting rules to get a deal. Also absent is Chinese President Xi Jinping, whose country tops the U.S. as the world’s No. 1 greenhouse gas polluter.

Even the host Brazil has drawn criticism from green groups for opening new oil and gas fields of its own in the run-up to hosting the COP30 talks.

The U.S. does not plan to send any high-level representatives to the COP30 conference, according to a White House spokesperson. Whether it intends to try to swing the talks from afar remains to be seen.

Trump and his Cabinet ministers led a pressure campaign that succeeded last month in delaying, and possibly killing, a vote on a global carbon tax for shipping that had seemed on a glide path for approval. The U.S. effort drew in help from other countries, including some EU members.

British Prime Minister Keir Starmer lamented that the global unity that had landed the Paris deal 10 years ago was being broken, not just by Trump but by Starmer’s opponents in the U.K.

“Sadly, that consensus is gone,” he declared.

But he said walking away from climate efforts would only raise energy costs for businesses and households and miss out on building new industries.

“This is not just a problem to be solved, but also an immense opportunity to be seized,” Starmer said.

The main economic beneficiary of the clean energy transition has, to date, been China, which has built the world’s largest production line of solar panels, electric vehicles, batteries, critical minerals and other products essential to greening the global economy.

“China is a country that honors its commitments,” Vice Premier Ding Xuexiang said at the podium Thursday.

He didn’t name Trump directly either but did make a case for a “sound environment” for global trade and cooperation.

“We need to strengthen international collaboration on green technology and industry, remove trade barriers and ensure the free flow of quality green products to better meet the needs of global sustainable development,” Ding said through a translator.