TOKYO (Kyodo) -- Japan's Defense Ministry is concerned that China is expanding the operational capabilities of its military over a wider area, its annual report said Tuesday, reflecting heightened vigilance against increasingly assertive activities by Chinese forces in the western Pacific.

Also taking into account security threats from North Korea and Russia, the ministry's 2025 white paper said that Japan is on track to meet its goal of raising defense-related outlays to 2 percent of gross domestic product, "fundamentally reinforcing defense capabilities" amid U.S. pressure for higher spending.

China has been "increasing operational capabilities in more distant areas," the document said, adding that it conducted over 1,200 landings and takeoffs from aircraft carriers in the Pacific in total last year.

Among the latest moves not covered in the paper are simultaneous operations by two Chinese aircraft carriers, the Shandong and Liaoning, in the western Pacific in early June this year, which Japan confirmed for the first time ever in the waters.

The paper, summarizing the nation's security challenges and defense activities in the year ended this March, said China's "intensified military activities" have led to a situation that could "seriously impact Japan's security, which is a cause of grave concern."

China is also trying to enhance its capabilities to carry out "gray zone" operations, aggressive actions that fall short of armed attacks, by strengthening coordination between the military and the People's Armed Police Force, such as the coast guard, the paper said.

"Overall, we kept our serious view unchanged on the current security environment," which is "the most severe and complex" in the post-World War II era, a government official told reporters.

The paper also said that China may have "rehearsed some parts of military operations toward the reunification with Taiwan, including invasion operations," in surrounding areas of the self-ruled democratic island that Beijing regards as a breakaway province to be brought into its fold.

In Beijing, Foreign Ministry spokesman Lin Jian said China has expressed "strong dissatisfaction and firm opposition" and lodged "a serious protest" over the white paper, claiming it reflects the "wrong perception" and "interferes" in its internal affairs.

Noting this year marks 80 years since Japan's surrender in World War II, Lin urged Tokyo to "deeply reflect on its historical crimes, draw lessons from history and stop finding excuses" for its own military buildup by exaggerating tensions in its neighborhood.

Regarding North Korea, the Japanese document described it as "posing an even more grave and imminent threat to Japan's security than before," with Russia's military activities in the Indo-Pacific region "posing a strong security concern," both the same expressions as in the 2024 report.

Russia and North Korea have been stepping up their military partnership amid Moscow's prolonged full-scale invasion of Ukraine since 2022, which North Korean troops have joined, while Pyongyang is continuing its missile and nuclear weapons development.

The paper pointed to the possibility that Pyongyang would receive military assistance from Moscow, such as "the transfer of nuclear and missile technologies."

Japan decided in 2022 to gradually increase its defense expenditure including related costs for the following five years with a target of 2 percent of GDP in fiscal 2027.

The nation's annual defense budget had long been capped at around 1 percent of GDP, or around 5 trillion yen ($34 billion) under its war-renouncing Constitution.

Meanwhile, U.S. President Donald Trump has been adding pressure on allies since taking office in January with his "America First" pledge, prodding NATO members to vow to invest 5 percent of GDP for defense and related expenses by 2035.

In the white paper, the Defense Ministry emphasized that it has secured "the necessary and sufficient budget," with outlays in fiscal 2025 totaling 9.9 trillion yen, equivalent to 1.8 percent of GDP in fiscal 2022.