Chinese and Russian military units will participate in a series of joint activities before year's end, and will strengthen cooperation in anti-missile defense, the Ministry of Defense said on Thursday.

The two militaries will conduct anti-terrorism drills in the Ningxia Hui autonomous region from Dec 2 to 13, said Senior Colonel Wu Qian, the ministry's spokesman.

Several Chinese pilots are in Russia learning to fly the Russian Sukhoi Su-35 fighter jet, Wu said. The Su-35 is Russia's most advanced fighter in use. Four of the planes were purchased by China and delivered last December.

"The Su-35 deal is part of Sino-Russia military cooperation, and pilot training and other areas of cooperation are going smoothly," Wu said.

The two militaries will also hold their second joint computer-assisted anti-missile drill from Dec 11 to 16 in Beijing. The goal is to "jointly train for antimissile combat, from planning and preparation to launch command and firing coordination", Wu said.

The People's Liberation Army Air Force is organizing the drill, and "both sides are now undergoing preparations for the exercise", he said, adding that the drill is for "responding to sudden and provocative ballistic or cruise missile attacks" on countries' territory.

"In the future, the Chinese and Russian militaries will strengthen cooperation in anti-missile defense," he said.

Li Xing, a professor specializing in Sino-Russian relations at Beijing Normal University, said the frequent and practical military cooperation between China and Russia is a "normal and logical extension of their comprehensive strategic partnership".

Li said the countries' surrounding regions - from the South China Sea to the Baltic Sea - are not entirely stable.

"Therefore, China and Russia have the need to improve their combat capability through cooperation," he said.

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