After Russia fired more than 70 missiles at Ukraine on Friday, the grid operator said: "Considering this is already the ninth wave of missile strikes on energy facilities, the restoration of power supply may take longer than before."

"Priority will be given to critical infrastructure facilities: hospitals, water supply facilities, heat supply facilities, and sewage treatment plants," it said.

(Reporting by Olena Harmash; writing by Tom Balmforth; editing by Timothy Heritage)