Russia's emergency ministry issued a tsunami warning on Friday for the Kuril Island chain after a powerful quake struck off Japan, officials said.
"A potential tsunami warning is declared" for the Kuril chain that includes four islands claimed by Japan, a spokeswoman for regional emergencies ministry said.
"People are being evacuated," spokeswoman Yekaterina Potvorova said, adding that ships had been ordered to leave ports.
Potvorova played down the potential threat of the tsunami, saying that waves were expected to reach around two metres (6.6 feet).
The tsunami warning does not include the nearby Sakhalin Island, she added.
Russia's territorial dispute with Japan surrounds the Kuril chain's southernmost four islands -- known in Russian as Iturup, Shikotan, Habomai and Kunashir -- which are still claimed by Tokyo and collectively known in Japan as the Northern Territories.