SHANGHAI, May 20 -- Chinese President Xi Jinping and his Russian counterpart Vladimir Putin attended a joint naval exercise launch in Shanghai on Tuesday.

Xi welcomed Putin at the naval port before the two leaders addressed the honor guard. They also met officers from the two sides.

The previous two naval exercises were held in 2012 and 2013. As an important part of cooperation between the two militaries, this year's exercise will show the sides' resolve in responding to threats and challenges as well as safeguarding regional security and stability, Xi said.

The exercise will also display the new level of strategic mutual trust and coordination between the two countries, Xi said.

Putin noted the friendship between the two militaries, which was forged during World War II.

The military relationship is an important part of the Russian-Chinese comprehensive strategic partnership of coordination. In the new era, the two militaries should enhance cooperation and join to tackle various threats and challenges to safeguard peace and stability of the region and the world as a whole, Putin said.

The seven-day exercise will run until May 26 in the northern part of the East China Sea.

Navies of the two countries will conduct operations in air defense, anti-submarine as well as maritime attack and the use of weapons to improve their capacity in coping with maritime security threats.

A total of 14 vessels, two submarines, nine fixed-wing aircraft as well as helicopters and special forces are taking part in the week-long exercise.

Both China and Russia dispatched ships, including China's Zhengzhou and Ningbo missile destroyers and Russia's Varyag missile cruiser.