Putin has played a major role in facilitating a peace accord between Azerbaijan and Armenia, hosting a meeting last November between Aliyev and Armenian Prime Minister Nikol Pashinyan.

In Ukraine’s second city, Kharkiv, authorities reported Russian military vehicles were on the move. Street clashes erupted in various districts. Pictures on social media showed two Russian vehicles on fire.

The city of 3 million endured a second night of shelling, with residents hunkering down in basement shelters and the city’s deep underground metro.

Among the strategic sites captured on the first day of the assault was the Chernobyl nuclear power station north of Kyiv, where staff still oversee the plant, though no reactors are in operation 36 years after the world’s worst nuclear accident.