The ongoing Russian invasion of Ukraine may lead to stronger military ties between Beijing and Moscow, the Japanese government said in its annual defense report released Friday, as Russia's rift with Western nations over the war deepens.

"For Russia, which is internationally isolated and has worn out its ground forces due to the aggression against Ukraine, the importance of political and military cooperation with China could increase," the Defense Ministry white paper said in a new chapter focused on the issue.

It is necessary to "monitor with concern the possibility that China-Russia military collaboration would deepen," the report said, adding that such a development could have a "direct impact" on the security environment surrounding Japan.

Photo taken in Mykolaiv, southern Ukraine, on July 18, 2022, shows the regional government's headquarters hit by a Russian cruise missile attack. (Kyodo) ==Kyodo

The first report under Prime Minister Fumio Kishida's government came amid a confrontation between Russia and the Group of Seven nations including Japan, with the war in Ukraine showing no signs of abating despite U.S.-led economic sanctions on Moscow, which China has not joined.

Beijing and Moscow have continued to take concerted action since the launch of the Russian invasion of the former Soviet republic in late February, including a joint bomber flight over the Sea of Japan, the East China Sea and the Pacific in late May.

The report criticized the Russian invasion for creating an "unprecedented" situation in which Moscow is "overtly conducting military acts incompatible with international law and order, and claiming the lives of innocent people."

To tolerate such acts could encourage "the wrong implication" that unilaterally changing the status quo will be allowed in other regions including Asia, and therefore Japan and the international community should never overlook it, the report said.

The statement was a tacit reference to China, which the report says is expanding its military activities in the maritime and aerial domains, especially in the East China Sea, and "engaging in unilateral and coercive attempts to change the status quo based on its own assertions."

On maritime issues where its interests conflict with others, Beijing "continues to act in an assertive manner, which includes dangerous acts that could cause unintended contingencies," the white paper said.

Chinese military activities, along with "insufficient transparency" in the country's defense policies, are "a matter of grave concern" for the region and international community, it added.

For the second straight year, the report said that stabilizing the situation surrounding Taiwan is not only important for Japan's security but for the stability of the international community.

Supplied photo shows the cover of Japan's 2022 defense white paper. (Photo courtesy of the Defense Ministry)(Kyodo)

Beijing regards the self-ruled democratic island as a renegade province to be reunified with the mainland.

"Regional tensions are mounting, with China showing its readiness to achieve reunification with Taiwan by force," Defense Minister Nobuo Kishi told a press conference after the release of the report.

China lambasted Japan later Friday, saying Tokyo in the defense report smeared Beijing's defense policy as well as legitimate maritime activities and interfered in the Taiwan issue, an internal affair.

"China expresses its strong dissatisfaction with and firm opposition to" the attitude by Japan, Foreign Ministry spokesman Wang Wenbin said, adding the government has already lodged a "solemn representation" with Tokyo.

On North Korea, the document said the nation has repeatedly launched missiles "with an extremely high frequency and in a new manner" since the beginning of the year, and its actions pose "grave and imminent threats" to Japan's security.

Pyongyang may engage in "further provocations," the report said, suggesting the country could carry out what would be its seventh nuclear test and its first since 2017.

To respond to the increasingly severe security situation surrounding Japan, the paper indirectly called for an increase in the defense budget, which has long been capped at around 1 percent of the nation's gross domestic product, or about 5 trillion yen ($36.2 billion).

Among the G-7 countries, as well as Australia and South Korea, Japan ranks lowest in terms of defense expenditure as a percentage of GDP, with per capita spending ranging from around a third to a half when compared with the other nations including Britain, France and Germany, according to the report.

The ruling Liberal Democratic Party, led by Kishida, is looking to lift Japanese defense spending over the next five years to an amount equivalent to 2 percent of GDP or more, a target that members of the North Atlantic Treaty Organization strive to meet.

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