China receives advanced Sukhoi fighter jets from Russia

The South China Sea dispute concerns the territory and sovereignty of ocean areas and strategically located island chains, Paracel and Spratly, that several countries claim in whole or in part.

China's claims rest on a 'nine-dash line' which the Hague recently invalidated by ruling that there is no legal basis to it.

Sino-Russian naval exercises come at a tense time in these contested waters.

Sino-Russian ties have been significant for years but they were strengthened when sanctions were imposed on Russia in 2014 post Crimea's annexation.

The US decision to install a High-Altitude Missile system in South Korea despite opposition from Russia and China brought them closer.

Over the last decade, China in concert with Russia used its veto power at the UN 6 times challenging Western leadership.

China conducts counter-terrorism exercises with Russia on an annual basis.

The joint military exercises were recently held in September 2016. This was the seventh joint naval drill conducted by China and Russia since 2005.

The two countries also participate in trilateral and multilateral exercises under Shanghai Cooperation Organization to improve their tactical and operational capabilities.

In 2015, Joint Sea Drills were conducted partially in the Mediterranean and in the Sea of Japan.

According to a US Department of Defence report, phase one of the joint drills focused on combating terrorism and protecting lines of sea communication.

Phase 2 comprised of joint air defence drills, simultaneous amphibious landings and anti-surface ship drills.

In a sign underscoring deepening military ties, China and Russia will hold joint naval exercises in the South China Sea.

According to China's Defence Ministry spokesman the drill will "enhance the capabilities of the two navies to jointly deal with maritime security threats".

The announcement comes on the heels of an unfavourable ruling towards China at the International Tribunal of Hague.

After a delay of two years, fearing that its jet will loose value after the unveiling of the J-20 stealth fighter by Chinese military, Russia delivered four Sukhoi Su-35 fighter jets to China.

Su-35s are an advanced version of the Su-30s used by the Indian Airforce.

According to reports, the delivery was made on 25th December, 2016.