"We continue to raise the alarm over the humanitarian impact of escalating violence across parts of the Middle East, which is driving rising civilian casualties, damage to civilian infrastructure and growing displacement of people," the secretary-general's spokesman Stephane Dujarric told a press conference.

He added that the United Nations was "particularly concerned by the number of reports of recent strikes on oil facilities, which could have serious environmental consequences across the region, with immediate possible impacts on safe water, on air that people need to breathe, and on food."

Bahrain's interior ministry had said Sunday that an Iranian drone attack also damaged a water desalination plant, which is essential infrastructure for the country's economy and drinking water supplies.

"We reiterate again that all possible precautions must be taken to protect civilians from the impact of hostilities and to avoid damage to health facilities, schools, water systems and other essential infrastructure," Dujarric said.

Several oil facilities in Iran were targeted by Israeli strikes Sunday, and Iran has also launched strikes on oil facilities in the region.