China's coast guard could step up armament and provocations around the Japanese-controlled Senkaku Islands in the East China Sea following the enforcement of a controversial Chinese law, a Japanese Defense Ministry think tank warned Friday.

The National Institute for Defense Studies said in an annual report that military competition between the United States and China in the Western Pacific is likely to further increase under a "new Cold War" between the two powers.

The institute published the report after Beijing on Feb. 1 enforced a law that allows the China Coast Guard to use weapons against foreign ships the country sees as illegally entering its waters, in what critics say is an attempt to seize the Senkakus, which China claims and calls Diaoyu.

File photo taken in September 2012 shows the Senkaku Islands in the East China Sea. (Kyodo)

"(Chinese President) Xi Jinping's leadership is stepping up efforts to strengthen challenge, based on force, to Japan's sovereignty" over the islands, said the report, titled East Asian Strategic Review 2021.

"Looking ahead, it requires strong concerns and alert that Chinese coast guard vessels could further build up armament and carry out more provocative acts in waters around the Senkakus," it said.

Masafumi Iida, head of a division at the institute's Regional Studies Department and one of the authors of the report, said, "(Chinese) law enforcement against Japanese fishing boats will likely become even more apparent."

"Last year there were signs as Chinese coast guard vessels followed and approached Japanese fishing boats," Iida told reporters. "It is possible that China could create an environment that is advantageous numerically for its vessels although they currently have around four near the Senkaku Islands."

There are 12 Japan Coast Guard vessels that are dedicated to protecting the uninhabited islets.

Referring to simmering tensions between the United States and China, the report said a "new Cold War" is expected to intensify as the People's Liberation Army seeks to deny the U.S. military's access to China in the event of contingencies.

The report cites a Chinese exercise from January to February during which a PLA Navy fleet consisting of a destroyer and three other vessels traveled to the Western Pacific through the South China Sea and the Bashi Channel, and then returned to the South China Sea after nearing Guam.

As U.S. B-52 bombers left Andersen Air Force Base on Guam last year, there were concerns of a possible decline in the country's Indo-Pacific region commitment once touted as a deterrence strategy against adversaries in Asia.

A U.S. B-52 strategic bomber flies over the U.S. Osan Air Base, south of Seoul, on Jan. 10, 2016. (Kyodo)

However, the report analyzes that the United States' move is in line with the 2018 National Defense Strategy, making its operations unpredictable.

Moreover, the United States has deployed B-1Bs in the Western Pacific that could install the latest long-range missiles, which the B-52H could not, as the report cites a U.S. Air Force person as saying it is the "best fit" for the Pacific area.

The report interprets the deployment as a containment strategy against China's PLA Navy.

The world is embroiled in the race between the two big powers, the United States and China, the report said, adding that countries, including in Europe, have started to pave the way for "strategic autonomy," meaning they aim not to be dependent on the two nations.

Australia, another important actor in the Indo-Pacific, is also seeking strategic autonomy as its relationship with China is deteriorating, but the report assesses that there has been no concrete outcome.

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