Russia's defense ministry has said it conducted drills using a surface-to-ship missile system on the Kamchatka Peninsula and the Kuril Islands in Russia's Far East.

The announcement comes as the Russian Pacific Fleet's forces began large-scale drills in the Far East last Friday.

The defense ministry said on Wednesday that eight Russian Tupolev-22M3 bombers carrying long-range missiles flew over the neutral waters of the Sea of Okhotsk and the northern part of the Sea of Japan.

In 2016, Russia deployed surface-to-ship missile systems on the islands of Etorofu and Kunashiri, which are part of the four islands Japan calls the Northern Territories.

Russia issued navigation warnings, saying it would conduct missile drills in waters around Etorofu Tuesday through Saturday.

But the Russian side has not revealed whether Wednesday's exercise was held in the Northern Territories.

Russia controls the islands. The Japanese government maintains they are an inherent part of Japan's territory. It says the islands were illegally occupied after World War Two.