A woman crosses the street as anti-tank constructions are seen in central Kyiv, Ukraine March 7, 2022.
A woman crosses the street as anti-tank constructions are seen in central Kyiv, Ukraine March 7, 2022. Reuters / GLEB GARANICH

The United States and its allies on Monday urged Russia at the United Nations to allow safe passage to civilians in besieged Ukrainian cities and aid to areas of fighting, saying the humanitarian crisis in Ukraine was rapidly deteriorating.

Envoys from many countries including the United States, Ireland and France as well as U.N. aid chief Martin Griffiths sounded the alarm over the rapidly rising number of civilian casualties, including women and children and displaced people.

"We need Russia's firm, clear, public and unequivocal commitment to allow and facilitate immediate, unhindered humanitarian access for humanitarian partners in Ukraine," U.S. Ambassador to the United Nations Linda Thomas-Greenfield said at the U.N. Security Council meeting called to discuss the humanitarian crisis.

Russia had offered Ukrainians escape routes to Russia and Belarus, its close ally, early on Monday after weekend evacuation ceasefire attempts failed.

"I don't know of too many Ukrainians who wish to seek refuge in Russia. This is hypocrisy," France's ambassador Nicolas de Riviere said.

More than 1.7 million people have fled Ukraine, many Western companies have pulled out and the West has imposed harsh sanctions on Russian banks and President Vladimir Putin.

Vassily Nebenzia, Russian envoy to U.N., accused Ukrainian authorities of not allowing civilians to flee.

Moscow, which denies targeting civilians, has vowed to press ahead with the campaign it launched on Feb. 24 and calls a "special military operation".

Griffiths, the U.N. aid chief, told the meeting all parties must take constant care to spare civilians, who should be allowed safe passage to wherever they would like to flee. Humanitarian corridors should also be established, he said.

"Civilians in places like Mariupol, Kharkiv, Melitopol, and elsewhere desperately need aid, especially life-saving medical supplies," he said.

Russian forces pressed on with their sieges and bombing of Ukrainian cities on the 12th day of the war. In the encircled southern port city of Mariupol, hundreds of thousands of people remained trapped without food and water under regular bombardments.

Russia's growing reliance on longer-range strikes on Ukrainian targets is increasing the number of civilian casualties and damage to civilian infrastructure, the Pentagon said on Monday.