A PHILIPPINE Coast Guard (PCG) ship was now patrolling off Escoda Shoal in the West Philippine Sea, the National Security Council (NSC) has reported.

In a radio interview on Thursday, NSC spokesman Assistant Director General Jonathan Malaya rebutted claims that the Philippines has surrendered its territorial control on Escoda after the withdrawal of another PCG ship, the BRP Teresa Magbanua, early this month.

"Definitely, I can say with confidence na hindi po tayo umatras dyan in the sense na parang ibinigay natin sa (that we did not retreat and gave it to) China. Nagkaroon lang po tayo ng (we just had a) repositioning," Malaya said.

The Teresa Magbanua had to sail back to its home port in Palawan to resupply and to repair the damage to the vessel after it was rammed by a bigger China Coast Guard (CCG) ship last August.

Malaya said that National Security Adviser Eduardo Año made it clear that there would be a relief ship for the Teresa Magbanua.

Escoda Shoal is 75 nautical miles from Palawan and is well within the Philippine exclusive economic zone (EEZ).

"May Coast Guard vessel na po tayo na nagpapatrolya sa Escoda Shoal, so ang ginagawa naman po nung ating Coast Guard vessel ay bantayan, siguruhin na walang reclamations, siguruhin na walang ilegal na nangyayari dyan sa Escoda Shoal (We already have a Coast Guard vessel patrolling in Escoda Shoal. What our Coast Guard ship is doing is that it is guarding and ensuring that there will be no reclamations and other illegal activities in Escoda Shoal)," Malaya said.

"So nagkaroon po kami ng shift sa aming communications na hindi na po natin ipapaalam but we can assure the Filipino people na hindi po natin ibinigay ang Escoda Shoal (we had a shift in our communications, we will no longer give details [on the ship's whereabouts] but we can assure the Filipino people that we did not give away Escoda Shoal)," he said.

Also on Thursday, media outlets in Tokyo reported that a Japanese warship cruised through the Taiwan Strait for the first time to assert its freedom of navigation.

The ship made the passage a week after a Chinese aircraft carrier sailed between two Japanese islands near Taiwan.

Japan's top government spokesman Yoshimasa Hayashi declined to comment on the reports at a regular briefing because they concern military operations.

The United States and its allies are increasingly crossing the 180-kilometer Taiwan Strait to reinforce its status as an international waterway, angering China.

The Sazanami destroyer made the unprecedented passage on Wednesday, several media outlets said.

Military vessels from New Zealand and Australia also sailed through the fiercely contested waterway on the same day, Wellington's defense ministry said on Thursday.

A defense official told AFP that one of its ships made its first passage through the Taiwan Strait in seven years, alongside an Australian guided missile destroyer to assert the "right of freedom of navigation."

The official added the mission was not conducted with Japan.

Japanese media said the three nations planned to conduct military drills in the contested South China Sea.

Last week, China's Liaoning aircraft carrier sailed between two Japanese islands near Taiwan for the first time, accompanied by two destroyers.

The ships entered Japan's contiguous zone — an area up to 24 nautical miles from the country's coast — Tokyo said, calling the incident "totally unacceptable." China said it had complied with international law.

It followed the first confirmed incursion into Japanese airspace by a Chinese surveillance aircraft in August.

The Yomiuri Shimbun daily cited unnamed government sources as saying Prime Minister Fumio Kishida had instructed Wednesday's Taiwan Strait journey over concern that doing nothing following China's intrusions could encourage Beijing to take more assertive actions.

Beijing views Taiwan as a renegade province and claims jurisdiction over the body of water that separates the island from China.

But the US and many other countries argue their voyages are usual, citing freedom of navigation.

China this month accused Berlin of heightening security risks in the Taiwan Strait, a day after two German navy ships sailed through the waters.

On Wednesday, China test-launched an intercontinental ballistic missile into the Pacific Ocean in its first such exercise in decades.

Japan said it had not been given advance notice of the test, with Hayashi expressing "serious concern" about China's military build-up in comments he reiterated on Thursday.

"China's military intrusion into our territorial airspace and other incidents has been happening one after another in a short period of time," Hayashi said.

Japan will do its "utmost in patrolling and monitoring" the situation, he added.

Taiwan's defense ministry said Thursday that 43 Chinese military aircraft and eight naval vessels were detected around the democratic island within a 24-hour period.

Beijing has said it will never renounce the use of force to bring Taiwan under its control, with Chinese leader Xi Jinping in recent years upping the rhetoric of "unification" being "inevitable."

In response, Taiwan has strengthened economic and political ties — most notably with the United States, its biggest weapons provider — while increasing its defense budget.

Bec Strating, professor of international relations at La Trobe University, said Japan's reported Taiwan Strait transit "is part of a broader pattern of greater naval presence by countries in and beyond Asia that are concerned about China's maritime assertions."

"Japan in particular has been dealing with China's 'grey zone' tactics in the East China Sea," including an increasing number of coastguard vessels sailing close to disputed islands, she told AFP.

Grey-zone tactics are actions that serve to exhaust a country's armed forces, military experts say.

Kishida's ruling party will hold a leadership election on Friday that will be a de facto vote to decide Japan's next prime minister, with candidates debating issues including regional security.