A Japanese warship sailed through the Taiwan Strait for the first time in decades, as tensions grow with China

• A Japanese destroyer crossed the Taiwan Strait for the first time in decades, per reports.
• It transited at the same time as Australian and New Zealand naval vessels, reports said.

A Japanese destroyer sailed through the Taiwan Strait for the first time in decades, Japan's Yomiuri newspaper reported, citing Japanese government officials.

The JS Sazanami, a destroyer operated by Japan's Maritime Self-Defense Force, or MSDF, entered the strait from the East China Sea on Wednesday morning and completed its journey that evening, unnamed officials told the outlet.

The report said it was the first time a Japanese naval vessel had passed through the strait since the Self-Defense Force was established, which was in 1954.

The officials said that Japan's prime minister, Fumio Kishida, had ordered the move as a countermeasure to China.

Kyoto News, Japan's news agency, and NHK, Japan's public broadcaster, also reported on the development.

During a press conference on Thursday, Japan's chief cabinet secretary, Yoshimasa Hayashi, said he would refrain from making a comment on the reports but said that China's military activities around Taiwan had been "expanding" and that Japan was looking at the situation with "very strong" interest.

Australian and New Zealand naval vessels also transited through the strait at the same time, ahead of joint exercises with the MSDF in the South China Sea, the reports said.

An Australian defense spokesperson told Business Insider that two of its naval vessels completed a routine transit of the strait and added that Australian Defense Force activities are conducted in accordance with international law.

"Our deployments to the region demonstrate our commitment to support an open, stable, and prosperous Indo-Pacific," they said.

Japan's foreign affairs ministry and New Zealand's defense ministry didn't immediately respond to requests for comment.

It's not the first time in recent weeks that international vessels have crossed the Taiwan Strait.

Two German warships sailed through earlier this month for the first time in two decades, with the country's prime minister saying they had a right to transit.

German Defense Minister Boris Pistorius said during a press conference at the time that "international waters are international waters."

He added: "It's the shortest and, given the weather conditions, the safest route. So we are passing through."

The US and its allies and partners, including Taiwan, maintain that the strait is open for freedom of navigation — but China doesn't see it quite the same way.

During a press conference on Wednesday, China's foreign ministry said it was "highly vigilant on Japan's political intention behind this move."

Foreign Ministry spokesman Lin Jian told reporters that "the Taiwan question concerns China's sovereignty and territorial integrity," adding that it is the political foundation of China-Japan relations and a red line that must not be crossed.

China maintains that it has indisputable sovereignty over Taiwan, an autonomous island democracy, and routinely applies military, economic, and diplomatic pressure with the threat of force to achieve unification ever-present.

According to updates shared by Taiwan's defense ministry, China's aircraft, vessels, and ships now operate around Taiwan almost daily, sometimes crossing the median line in the strait and causing Taiwan to scramble its planes.

The latest updates show an uptick in Chinese aircraft and vessels being deployed and crossing Taiwan's air defense identification zone.

Military experts say that signs — like China's rapid modernization of its armed forces over the past two decades and drills around Taiwan — point to potential military action to seize the island by force, possibly in just a few years.