Ukrainian nationals living in Japan have spoken of their anxiety following Russia's invasion of their country, with many voicing concern for family members and friends back home.

"My elderly mother is unable to see very well. It would be hard for her to move around, and I wonder if there will be a place for her to evacuate," said Olena Kryvoruka, 42, who runs a music school in Asahikawa, Hokkaido, after Russia launched its invasion Thursday.

As tensions escalate, with Russian troops approaching the capital Kyiv and having taken control of the Chernobyl nuclear power plant in the north, Ukrainian Ambassador to Japan Sergiy Korsunsky on Friday expressed his anger over the number of casualties in his homeland.