A 7.5-magnitude quake hit off Russia's Kuril Islands on Wednesday, the US Geological Survey said.
The quake hit at a depth of 59 kilometres (37 miles), USGS added.
The US National Tsunami Warning Center said it was "analyzing the event to determine the level of danger".
The Pacific Tsunami Warning Center said "only very small tsunami waves were generated by this earthquake and there is no further threat".
It had previously warned tsunami waves were possible for coasts in the region.
The four southernmost islands of the Kuril chain -- Habomai, Shikotan, Etorofu and Kunashiri -- have been disputed between Moscow and Tokyo since the end of World War II.
The Kurils are known as the Northern Territories in Japan.