The Russian military on Tuesday launched massive naval and air drills spanning across both hemispheres and including China in joint maneuvers.

The “Ocean-24” exercise spans the Pacific and Arctic Oceans, the Mediterranean, Caspian and Baltic Seas and involves over 400 warships, submarines and support vessels, more than 120 planes and helicopters and over 90,000 troops, the Russian Defense Ministry said in a statement. The maneuvers will continue through Sept. 16, the ministry said.

Russian President Vladimir Putin said in comments to military officials that the war games are the largest of their kind in three decades, and that China's warships and planes were taking part. China confirmed that on Monday, saying the two countries' navies would cruise together in Pacific, but gave no details.

A total of 15 countries have been invited to observe the drills, Putin said, without naming them.

“We pay special attention to strengthening military cooperation with friendly states. Today, in the context of growing geopolitical tensions in the world, this is especially important,” Putin said.

The Russian leader accused the United States of “trying to maintain its global military and political dominance at any cost," seeking “to inflict a strategic defeat” on Russia in its war with Ukraine and to “break the established security architecture and balance of power in the Asia-Pacific region.”

“Under the pretext of countering the allegedly existing Russian threat and containing the People’s Republic of China, the United States and its satellites are increasing their military presence near Russia’s western borders, in the Arctic and in the Asia-Pacific region,” Putin said, stressing that “Russia must be prepared for any development of the situation.”

Russia and China, along with other U.S. critics such as Iran, have aligned their foreign policies to challenge and potentially overturn the Western-led liberal democratic order.

With joint exercises, Russia has sought Chinese help in achieving its long-cherished aim of becoming a Pacific power, while Moscow has backed China’s territorial claims in the South China Sea and elsewhere.

Russia’s Defense Minister Andrei Belousov said the drills are aimed to train “repelling large-scale aggression of a potential enemy from ocean directions, combating unmanned boats, unmanned aerial vehicles, defending naval bases, conducting amphibious operations and escorting transports.”