" With the death toll rising, we are seeing images of fear, anguish and terror in every corner of Ukraine," he tweeted.

" The protection of civilians must be priority number one. International humanitarian and human rights law must be upheld," he said.

Ukrainian roads are operating as usual, while all ports and the sky over the country are closed, Mikhail Podolyak, an adviser to the head of the Ukrainian Presidential Office, said on Friday.

"Key roads and main highways are operating as normal. Of course, there are some traffic jams on them in one direction or another, because panic sentiments, unfortunately, they also exist... As for ports, all ports are closed. As for air traffic, the sky is closed," Podolyak told a briefing.

Railway traffic is generally operating as scheduled, he added.

"Of course, commercial banks are closed but the state banking sector is working. Banks close their branches only in places of military clashes," Podolyak said. Volodymyr Zelenskyy remains in the capital, Podolyak said.

"He must show what the resilience of the Ukrainian people is," he added.