A Taiwanese minister made a rare trip this week to a remote island in the South China Sea at a time when tensions in the region remain high.

Ocean affairs council minister Kuan Bi-ling travelled to Itu Aba – also known as Taiping Island – to observe exercises carried out by the coast guard.

Itu Aba is the largest naturally occurring island in the disputed Spratly Islands in the South China Sea – which is claimed by China, Vietnam and the Philippines. In a statement, Taiwan’s coast guard described the exercise as a “humanitarian relief, medical evacuation and marine pollution removal” operation.

Taiwan’s official Central News Agency said that it was the first time in seven years that a Taiwanese minister had visited Itu Aba. This visit by the minister comes amid tensions between the two countries. China claims Taiwan as its own while Taiwan says it is an independent, sovereign nation.

One of the exercises that Ms Kuan observed involved a mock interception at sea. According to the coast guard, the officers simulated stopping a cargo ship that ignored repeated calls.

Armed personnel then boarded the vessel to take control. Authorities said the scenario reflected real risks in busy and disputed waters.

“In order to safeguard the nation’s rights and national security, the cargo vessel was escorted back to Taiping Island for further investigation,” the coast guard said.

A video released later showed officers in black gear moving through the ship and entering its control room. During the drill, one officer addressed a crew member directly, saying: “You have entered the waters under the jurisdiction of our country. Please cooperate with the investigation.”

Ms Kuan’s visit coincided with large US-Philippines military drills, which had already upset China. While those exercises were underway, China responded by sending a new amphibious warship into the South China Sea and moving an aircraft carrier through the nearby Taiwan Strait.

Taiping Island is located roughly 1,600km southwest of Kaohsiung and falls under the administration of Cijin district in the southern Taiwanese city, according to Focus Taiwan media outlet.

Taiping Island has a runway capable of handling military supply flights and a recently upgraded wharf that can receive large patrol vessels. Around 200 people live there, mostly coast guard members trained for both security and rescue work.

Despite these facilities, the island is not heavily fortified when compared to nearby outposts controlled by China.

Beijing has spent years expanding its presence across the South China Sea, building artificial islands and adding airstrips, radar systems and other military infrastructure. These moves have raised concern across the region and in Washington.

China maintains that its actions are justified and says it has the right to develop and defend what it considers its territory. Taiwan, however, rejects Beijing’s claims over it and continues to operate independently on the islands it controls.

The wider South China Sea remains one of the world’s most important waterways. Huge volumes of global trade pass through it each year. It is also a major fishing zone and is believed to hold significant oil and gas reserves beneath its seabed.

A 2016 decision by an international tribunal labelled Taiping Island a “rock” under the United Nations Convention on the Law of the Sea. This means Taiwan can claim resources only within 12 nautical miles of it, rather than 200 nautical miles if it were recognised as an “island”.

Taiwan presented its case to the tribunal, arguing that Itu Aba should be recognised as an “island”, saying it has the resources needed to support human life, including a supply of fresh water.

Both Taiwan and China have rejected the ruling of the tribunal and do not accept the arbitration case filed by the Philippines.

Taiwan argues Itu Aba can sustain life, while the 2016 tribunal ruled it does not, classifying it as a “rock,” which sharply limits its maritime rights.