Russian missile strikes on Ukraine's energy infrastructure have caused a massive power outage across Moldova, the country's deputy prime minister said on Wednesday.

"Massive blackout in Moldova after today's Russian attack on Ukraine's energy infrastructure," Andrei Spinu, who also serves as infrastructure minister, said on Twitter.

"Moldelectrica, TSO (transmission system operator), is working to reconnect more than 50 percent of the country to electricity."

There has been no response from Russia yet.