Geopolitical tensions, including the current crisis between Russia and Ukraine, could hamper international efforts to curb global warming even as time to tackle the problem is running out, U.S. climate envoy John Kerry said Friday.

Speaking at the annual Munich Security Conference, the former Secretary of State warned that the rise in the cost of energy stoked by the crisis may make consumers and governments wary of taking tough measures needed to reduce greenhouse gas emissions.

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“It’s not going to be positive because it’s going to distract rather enormously,” Kerry said of the current tensions.

“The prices of fuel will inevitably rise even more,” he said. “It will push people towards the path of least resistance, which we are already too much locked into, and that will bring about the path of greatest destruction.”

At the same time, Kerry said the situation could encourage some European nations such as Germany, which depend on Russian gas, coal and oil for much of their energy needs, to expand the use of renewable energy or seek other suppliers faster.

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“Will it spur transition? Yes, I think it will,” he told The Associated Press in a phone interview.

Kerry, who has led the Biden administration’s international climate diplomacy efforts, said the U.S. and European Union are in talks about their plans to prevent domestic producers suffering because of imports from countries without stringent emissions reductions measures.

Washington and Brussels hope to ensure their respective approaches to the problem are compatible, but potential trade conflicts loom with Russia and China, which strongly oppose any possible tariffs on their goods.

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“Any country that is serious about climate will not be passive about competing with countries that are not,” Kerry said.

″(Russia and China) want freedom to continue to produce dirty products, that’s unacceptable,” he added.

Still, Kerry noted that without Russia, China and other major emerging economies reducing their emissions of planet-warming gas, global goals to limit temperature rise by the end of the century can’t be met.

“It is dictated by simple mathematics and physics,” Kerry said during his comments at the Munich conference.

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Scientists have said emissions need to drop drastically this decade to prevent the worst impact of climate change.

“This is really the critical year during which we will either prove we’re serious and we’re going to try to do what we have to do in 10 years, or we can’t do it,” said Kerry. “In which case we will be spending trillions of dollars cleaning up the mess and trying to cope with the crisis.”

A U.N. science panel report currently being finalized and due to be published at the end of the month will likely highlight to governments the urgency to act, he said.

“I think it’s going to be quite dramatic in the picture it paints of how far behind we are.”