A magnitude eight earthquake has struck off Russia's Kamchatka Peninsula, sparking tsunami warnings from Japan and the US Tsunami Warning Centre.
The US Geological Survey said the earthquake was shallow, at a depth of 19.3km.
The epicentre was located 136km east-southeast of Petropavlovsk-Kamchatsky, a city in Russia's far east, USGS said.
The Japan Weather Agency said it expected a tsunami of one-metre to reach large coastal areas starting around 11am AEST.
The US Tsunami Warning System also issued a warning of "hazardous tsunami waves" within the next three hours along some coasts of Russia and Japan.