The US Embassy in Kyiv issued a security alert late on Thursday urging all American citizens in Ukraine to leave immediately.
The alert, which appeared to be in response to a deadly Russian attack on the Ukrainian city of Vinnytsia, asserted that large gatherings and organised events “may serve as Russian military targets anywhere in Ukraine, including its western regions”.
Ukrainian President Volodymyr Zelensky repeated his call for Russia to be declared a state sponsor of terrorism.
“No other country in the world represents such a terrorist threat as Russia,” Mr Zelensky said in his nightly video address.
“No other country in the world allows itself every day to use cruise missiles and rocket artillery to destroy cities and ordinary human life.”