UN High Commissioner for Refugees Filippo Grandi has said there are no winners in war but countless lives will be torn apart.

"We are gravely concerned about the fast-deteriorating situation and ongoing military action in Ukraine," Grandi said in a statement, adding that the humanitarian consequences on civilian populations will be devastating.

He said they have already seen reports of casualties and people starting to flee their homes to seek safety. "Civilian lives and civilian infrastructure must be protected and safeguarded at all times, in line with International Humanitarian Law."

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UNHCR is working with the authorities, UN and other partners in Ukraine and is ready to provide humanitarian assistance wherever necessary and possible.

"To that effect, security and access for humanitarian efforts must be guaranteed," said. Grandi

UNHCR is also working with governments in neighbouring countries, calling on them to keep borders open to those seeking safety and protection.

"We stand ready to support efforts by all to respond to any situation of forced displacement," he said.

Accordingly, Grandi said, they have stepped up their operations and capacity in Ukraine and neighbouring countries.

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"We remain firmly committed to support all affected populations in Ukraine and countries in the region," he said.