Vladimir Putin has ordered his Pacific Fleet to launch surprise war games to test their readiness for a retaliatory nuclear strike on the West.
Defence Minister Sergei Shoigu announced the unexpected drills in a seemingly deliberate show of strength to the West.
The Pacific’s Fleet’s firepower has been seen as Moscow’s main weapon in retaliatory strikes since Soviet times.
Putin’s war against Ukraine has already cost hundreds of thousands of lives.
The exercises based on naval base Vladivostok were expected to involve the firing of missiles and testing the readiness of nuclear-capable strategic bombers as well as the fleet’s submarines.
The war games also had more limited objectives such as repelling supposed enemy attacks on Sakhalin island and the Kuril chain north of Japan.
Japan asserts territorial rights to the Kuril Islands which were grabbed by Stalin in World War Two.
Last year, Russia suspended peace talks with Japan to protest Tokyo’s sanctions against Moscow over its action in Ukraine.
General Valery Gerasimov - the Kremlin’s most senior soldier - said Russia's naval forces would be put on high alert during the drills and deployed to training areas, where they will conduct combat exercises.
"The main goal of this check is to build up the ability of the armed forces to solve the tasks of repelling the aggression of a potential enemy from oceanic and sea areas," said Shoigu - a close Putin ally - on state TV.
“During the event, the Pacific Fleet will have to repel massive missile and air strikes, conduct exercises to search for and destroy submarines, perform torpedo and artillery firing and missile launches."
The move comes after it emerged Putin plans to send school-leavers as young as 18 into the war.
Russia will sign up the conscripts and send them directly to the front line as part of its regular army.
The new legislation was rubber stamped this week by Putin's obedient parliament.
It paves the way for the recruitment of hundreds of thousands of raw recruits.
