Quake strikes off Russia's east sparking tsunami alert

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.