The United States and Japan showcased their military force by flying more than 50 jet fighters over the seas near Tokyo this week amid rising tension with China and Russia.

The exercises included 12 of the most advanced F-22 stealth fighters, four F-35 stealth jets, and 13 F-15 jets of the US Air Force, according to a news release from the Japanese Defense Ministry on Thursday.

Twenty Japanese F-15 and F-2 fighters and three US reconnaissance and support aircraft joined the US fighter jets, according to a CNN report.

The US and Japanese warplanes flew over the Pacific Ocean, the East China Sea, and the Sea of Japan to strengthen their tactical abilities and "joint response capability," according to the Japanese Defense Ministry.

Despite announcing in a news release last month that it had sent 12 F-22s from the Hawaii Air National Guard to Kadena Air Base in Okinawa, the US Air Force did not immediately respond to a request for comment regarding the exercises this week.

According to a US statement, the F-22 fighter jets were in Japan to conduct "various missions to enhance operational readiness to defend Japan and ensure a free and open Indo-Pacific," the US statement said.

Additionally, this week, the US and Japanese maritime patrol planes practiced near the Senkaku Islands, a group of uninhabited islands that China also claims and calls the Diaoyus, as well as the Nansei Islands, the nearest Japanese territory to Taiwan.

According to a Japanese statement, the exercise was held to "strengthen the capacity of the Japan-US Alliance for effective deterrence."

The Chinese Coast Guard's patrols in the waters surrounding the islands were "an appropriate exercise of China's sovereign right," the Chinese Foreign Ministry claimed per CNN.

China, Russia Boost Military Presence in Japanese Territory

The presence of Chinese and Russian vessels in the territory of Japan has grown recently.

Tokyo said late last month that eight Chinese and Russian ships had been detected in the vicinity of Japan.

According to a news statement from the ministry, a five-ship Russian flotilla spent a week sailing close to Japanese islands, from Hokkaido in the north to Okinawa in the south.

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In late May, Beijing and Moscow also flew six strategic bombers over the Pacific, the East China Sea, and the Sea of Japan. The incident occurred when Tokyo was hosting a meeting of "the Quad," which includes Australia, India, and the United States, as reported by the Japan Times.

Japan, Britain Reportedly To Develop Next-Generation Jet Fighters

Meanwhile, three individuals informed Reuters that Britain and Japan are nearing an agreement to combine their next-generation Tempest and F-X fighter jets programs. The two nations hope to finalize a pact on a new joint project by the end of the year.

The program would be the first time Japan to work with Britain on a significant military program, going beyond expectations when industrial talks began five years ago.

According to one of the sources, Japan and Britain would work together as "equal" partners. He stated that it would cost tens of billions of dollars.

By the end of December, the effort to merge the British Tempest program and the Japanese F-X program, operated by BAE Systems PLC (BAES.L), had not been publicized.

The sources requested anonymity because they were not authorized to communicate with the media about the program.

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