The week-long "Shared Waters 2016" exercise reportedly involves a significant number of war ships, submarines, aircraft as well as helicopters and marine officers in amphibious armored equipment. It is designed as a rehearsal of sorts for defending a series of disputed islands in the South China Sea against invasion.

A simulated invasion of the islands in the South China Sea is reportedly also part of the military exercise, according to the Chinese state-run Xinhua news agency.

It is the fifth joint military exercise between the two nations. But it's the first of its kind to be held in the South China Sea, where territorial ownership over a number of islands is contested between China and several nearby countries in the region.

Competing claims of control

Vietnam and the Philippines in particular have been accusing China of building artificial islands to strengthen their military position, and gain control over the waters. China in the meantime accuses its neighbors of illegally occupying the islands, which it says have been Chinese territory for centuries.

Some of the islands are located much closer to the Philippines than to the Chinese mainland. Russia is the only world power that puts its support and weight behind China. Russia's Sputnik news agency quoted Vice Admiral Alexander Fedotenkov as saying that the goal of the naval partnership was "the security of peaceful activities across the world's seas and oceans and in the prevention of dangerous challenges."

The United States has repeatedly criticized China for aggressive involvement in the region. US President Barack Obama said that Beijing had to abide by a recent ruling by the International Court of Justice in The Hague, saying that China had to forfeit the majority of its territorial claims in the South China Sea.

Beijing has ignored the ruling, arguing that the court had no jurisdiction over it.

ss/gsw (dpa, AP)