June 29 (UPI) — Extreme heat that has been baking Europe over the last two weeks is at least partially responsible for hundreds of additional deaths, according to the United Nations’ health chief.

The continent has been gripped by a heatwave that has sent temperatures soaring from the high 90s to low 100s Fahrenheit since at least June 17, when Britain’s Met Office warned that a significant heatwave was developing across parts of Europe.

Since then, a number of European nations, including Germany, Belgium and the Netherlands, have set heat records, prompting officials to cancel outdoor events as well as issue warnings about dangerous temperatures.

World Health Organization Director-General Tedros Adhanom Ghebreyesus said Sunday in a statement that the high temperatures have been linked to more than 1,300 excess deaths reported across Europe since June 21.

“Heat stress is often called the ‘silent killer’ — and European homes, workplaces and schools were not built for these temperatures,” he said, urging European countries to “implement heat health action plans” as part of their broader agendas to protect their citizens against climate change.

Europe was the fastest-warming continent on Earth, heating at twice the global average, according to Ghebreyesus, who said that 150 million people were currently living under extreme heat that has shuttered schools, buckled power grids and killed hundreds.

“Driven by climate change and global warming, the phenomenon of the ‘once-in-a-generation’ heatwave is now occurring nearly annual,” he said.

“We were warned.”

France’s Health Ministry announced Sunday that since Wednesday, it has recorded about 1,000 additional deaths compared to those recorded in previous months, with the increases most pronounced in regions under a red alert due to high temperatures, including Normandy and Pays de la Loire.

Though all age groups were affected by the rising temperatures, about 85% of the deaths were observed in those 65 years of age and older, according to the ministry, which said there has been around a 40% increase in deaths at home.

“This observation serves as a reminder of the need for measures of solidarity toward people who are isolated or experiencing profound loneliness, including in highly urbanized areas,” it said.

The heatwave comes as efforts to curb climate change have faced recent setbacks. The International Energy Agency said in its State of Energy Policy 2026 report that regulatory rollbacks, particularly in the United States, were “the dominant force” last year, with stricter rules applied to 17% of regulated energy consumption compared with rollbacks affecting 30%.

“Europe’s savage heatwave has the fingerprints of the climate crisis all over it,” U.N. Climate Change Executive Secretary Simon Stiell said in an online statement late last week.

“Until humanity stops burning coal, oil and gas, extreme heat will keep getting worse. The solutions are clear: a faster shift to renewables, protecting forests and boosting climate resilience.”