Russia's Pacific Fleet drills came a week after Tokyo's Prime Minister Fumio Kishida visited Ukraine.

"In the waters of the Sea of Japan, missile boats of the Pacific Fleet fired Moskit cruise missiles at a mock enemy sea target," the ministry said on Telegram early on Tuesday.

It said two ships took part in the exercise.

"The target, located at a distance of about 100 kilometres (62 miles), was successfully hit by a direct hit from two Moskit cruise missiles."

Moscow said its naval aviation oversaw the "safety of the combat exercise."

Last week, Russia said two of its Tu-95 strategic bomber planes performed "flights in the airspace over neutral waters in the Sea of Japan."

The bomber jet flights came after Japan's Kishida visited Kyiv to meet with Ukrainian leader Volodymyr Zelensky.

Japan has joined Western allies in sanctioning Russia over its offensive in Ukraine.

Russia's far eastern Pacific coast is separated from Japan by the narrow Sea of Japan.