Russian S-300 and S-400 air defense missile systems are put in combat mode to practice hitting targets in the largest military drill the nation has held since the 1980s.
China is sending about 3,200 troops, 900 combat vehicles and 30 aircraft to join the drills at a Siberian firing range, a significant deployment that reflects its shift toward a full-fledged military alliance with Russian Federation.
The week-long exercise dubbed "Vostok-2018" also includes the Mongolian army.
Some experts see the war games as a message to Washington, with which both Moscow and Beijing have strained ties.
While Russia has clarified that the manoeuvres are not directed against other countries; North Atlantic Treaty Organisation said that it will monitor the exercise closely.
Russia's armed forces began the second day of its massive military exercises in the country's far east on Wednesday with a show of strength involving anti-aircraft and missile maneuvers.
China's participation will enhance its counterattack abilities and reinforce ties with Russia, Chinese government officials said Tuesday.
Russian President Vladimir Putin, who put the troops in the central and eastern military districts involved in "Vostok 2018" on alert in August, will personally supervise the march of the exercises after meeting yesterday with Chinese leader Xi Jinping.
Shoigu said that about 300,000 military personnel would take part, twice as many as the largest war games conducted by the Soviet Union: the Zapad-81 exercises in 1981.
About 36,000 Russian tanks and armoured vehicles, 1,000 warplanes, helicopters and drones, and 80 warships will be joined by 900 Chinese combat vehicles and 30 aircraft, underscoring a growing partnership between Beijing and Moscow to challenge American global hegemony.
" When asked if he was concerned about a potential military alliance between Russian Federation and China in the future, U.S. Defence Secretary Jim Mattis said he did not see the two countries aligned in the long-term".
"We're aware of Russia's right to sovereignty and to exercise in order to ensure their readiness", he said.
Putin is preparing his military for "warfare on a huge scale" to satisfy "delusions" that Russian Federation can defeat Western nations in a global conflict, according to an expert on his armed forces.
It fits into a pattern we have seen over some time: "a more assertive Russian Federation, significantly increasing its defense budget and its military presence".
No doubt, both Russian Federation and China relish the opportunity of flexing military muscle just as U.S. threats are heating up and tensions are at boiling point over Syria, where both countries have condemned past American and Western military actions targeting the Assad government.