Japan has voiced "severe concerns" over China and Russia's frequent joint air force activities around Japanese territory, Chief Cabinet Secretary Hirokazu Matsuno said Thursday.
"We will closely monitor the increasing cooperation between the two countries with a sense of concern," Matsuno, Japan's top government spokesperson, told a regular press conference, adding that Japan would "decisively protect" its territories.
The Russian Defense Ministry on Wednesday announced its military and Chinese counterpart conducted joint patrols of strategic warplanes over the Sea of Japan and East China Sea.
It said that the Tu-95 bombers of the Russian air force and the Chinese H-6K bombers flew over the Sea of Japan and the East China Sea during an eight-hour mission.
As part of the drills, the Russian bombers for the first time landed in China and the Chinese bombers flew to an air base in Russia, the ministry said in a statement. It noted that the joint patrols weren't directed against any other country.
Growing military cooperation
The exercise follows a series of joint drills intended to showcase growing military cooperation between Moscow and Beijing as they both face tensions with the United States.
In September, Beijing sent more than 2,000 troops along with more than 300 military vehicles, 21 combat aircraft and three warships to take part in a sweeping joint exercise with Russia.
The maneuvers marked the first time that China has sent forces from three branches of its military to take part in a single Russian drill, in what was described as a show of the breadth and depth of China-Russia military cooperation and mutual trust.
Defense cooperation between Moscow and Beijing has grown stronger since Russian President Vladimir Putin sent his troops into Ukraine on Feb. 24.
China has pointedly refused to criticize Russia’s actions, blaming the U.S. and NATO for provoking Moscow, and has blasted the punishing sanctions imposed on Moscow.
Russia, in turn, has strongly backed China amid the tensions with the U.S. that followed a visit to Taiwan by U.S. House Speaker Nancy Pelosi.