Strong statements on the need to combat climate change have become staple fare at global summits — a problem, like terrorism, that all leaders traditionally agreed needs to be tackled even if they differed on the details.
But the issue could become a stumbling block at a G-7 meeting of leading Western powers in Sicily this month, amid uncertainty over whether the U.S. will withdraw from the Paris Agreement on fighting global warming.
"We are working very hard, our Italian friends are working very hard on a strong outcome," Jochen Flasbarth, a senior official in Germany's environment ministry, said Thursday at the end of a two-week meeting on climate change in Bonn, Germany.
U.S. President Donald Trump pledged during the election campaign to "cancel" the Paris climate accord, which was widely hailed as a key step toward cutting planet-warming carbon emissions when it was agreed upon in 2015. The White House recently said it will make a decision about the Paris agreement after the G-7 summit that takes place in Taormina, Sicily on May 26-27.
Flasbarth said the Trump administration's position is also being felt in preparations for his country's hosting of the Group of 20 leading and emerging economies in Hamburg on July 7-8.
"There is some uncertainty, both for the communique under the G-20 presidency as well as the G-7 meeting, because the position of the U.S. with regard to climate change policy is still under review," Flasbarth said.
Experts expressed concern at the prospect that differences over climate change would prevent the G-7 leaders from agreeing on a joint declaration next week.
"It's not acceptable for the other six to have no mention of climate in the final G-7 communique," said Alden Meyer of the Union of Concerned Scientists, a veteran observer of international climate negotiations. He said if there's no agreement, the other six G-7 countries may issue their own statement on climate change.
The State Department declined to comment on Flasbarth's comments or the complications posed for other G-7 countries by the U.S. position.
A State Department official said in an emailed statement that the Trump administration was "reviewing the United States' international climate change policies" and had no decisions to announce.
The statement echoed the words of American officials whenever they were pressed about the U.S. plans at the climate talks in Bonn this month.
Other nations insisted they would move ahead with ambitious goals to curb global warming regardless of the U.S. stance.
"At this point in time, of course, the United States has not made that decision (to withdraw from the Paris accord)," said Fiji climate envoy Nazhat Shameem Khan, but added: "We will not stop our work even if the result is a negative one."
The Pacific island nation will chair an annual climate summit in Bonn on Nov. 6-17.
Karl Ritter in Rome and Josh Lederman in Washington contributed to this report.