KYIV: The World Health Organization on Monday warned that the upcoming winter would be "life-threatening" for millions of Ukrainians after a series of devastating Russian attacks on the country's energy grid.

"Put simply -- this winter will be about survival," Hans Kluge, regional director for Europe at the United Nations' health body, told reporters during his visit to Kyiv.

"This winter will be life-threatening for millions of people in Ukraine," he said.

Damage to Ukraine's energy infrastructure caused by numerous missile strikes "is already having knock-out effects on the health system and on the people's health," Kluge said.

Ukraine’s Zelenskiy warns of tough winter, reports war gains

He said that the WHO has recorded more than 700 attacks on Ukraine's health facilities since Russia's invasion began in February.

He pointed to "a clear breach" of international humanitarian law.

"Continued attacks on health and energy infrastructure mean hundreds of hospitals and health care facilities are no longer fully operational," Kluge said.

"We expect two-three million more people to leave their homes in search of warmth and safety," he warned.

"They will face unique health challenges, including respiratory infections such as Covid-19, pneumonia, influenza, and the serious risk of diphtheria and measles in under- vaccinated population."