"The reason is a simple one: unlike the rest of the world, Russian Federation thinks that a state of hostility now exists between it and Europe which is just as unsafe and threatening as during the Cold War, and it needs to prepare for warfare on a huge scale accordingly".
Amid growing recent tensions between Moscow and the West, NATO has said it will monitor the drills closely.
The week-long exercise dubbed "Vostok-2018" also includes the Mongolian army.
"The [Vostok 2018] exercise sends a signal to Washington and its allies - if United States continues to push [Russia and China], they will have to deepen military ties", he said.
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".
"Russia has very strong real combat abilities and the participation of the PLA in such a large-scale military exercise that is specially tailored for an anti-invasion war indicates China's intention to learn more valuable combat practices and lift its ability for joint combat", Song said.
China's participation in the exercises, known as the Vostok drills, exemplifies an overall expansion of collaboration with Russian Federation as an ally, the Kremlin has said.
Xi Jinping, left, met Vladimir Putin on the sidelines of the Eastern Economic Forum in Vladivostok.
The bulk of the troops taking part in the five-day drills in eastern Russia near the Chinese border are Russian: 300,000 vs. about 3,200 from China.
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Open trophy after beating Serena Williams of the United States of America in the women's final on day thirteen of the 2018 U.S. However, the world number one Williams received three code violations , therefore, meaning she was docked a game.
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The vehicle will be built in both Chongqing, China, and Saarlouis, Germany, a Ford spokesman said in an interview on Monday. Citing Trump's new tariffs , Ford on August 31 said it was dropping plans to ship the Focus Active from China to America.
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While losing Saturday's final to Japan's Naomi Osaka , Williams smashed her racket and called the umpire a "thief" and "liar". Williams' heated exchanges with an umpire at the tournament final this week have stirred the tennis world.
Last month, the Kremlin´s spokesman said Russia´s "ability to defend itself in the current worldwide situation which is often aggressive and unfriendly to our country is justified, essential and without alternative".
"It will be unprecedented in terms of geographic scope and the strength of command and control centers and forces due to participate", defence minister Shoigu said. They will feature more than 1,000 aircraft, about 36,000 tanks and other military vehicles and 80 warships.
"Imagine 36,000 military vehicles moving at the same time: tanks, armored personnel carriers, infantry fighting vehicles - and all of this, of course, in conditions as close to a combat situation as possible", Shoigu said.
Relations between Russian Federation and the West declined sharply in 2014 with Moscow's annexation of Crimea and the outbreak of a Kremlin-backed uprising in eastern Ukraine.
Moscow has increased the number of its large-scale military exercises in the Caucasus, the Baltic and the Arctic in recent years.
They also serve as an exercise in "military muscle-flexing" to Russia's global rivals.
At the same time the Kremlin has accused North Atlantic Treaty Organisation of expanding westwards and threatening Russian national security.
The war games are held a year after Russian Federation staged major drills in the country's west last September, unnerving neighbouring former Soviet republics.