A China coast guard vessel transits the East China Sea near the Senkaku Islands on Aug. 16, 2019. (Japan Coast Guard)

Beijing brushed aside Tokyo’s protests this week after publishing an official map that depicts disputed islets claimed by Japan in the East China Sea as Chinese territory.

China on Wednesday also reasserted its claims over the disputed Senkaku Islands, Foreign Ministry Mao Ning, a spokeswoman for China’s Ministry of Foreign Affairs, said at a regular news briefing.

The Senkakus, a string of five uninhabited islands and three rocks 280 miles west of Okinawa, are administered by Japan but claimed by both Taiwan and China, which refers to them as Diaoyu Dao.

China released the updated territorial map that referred to the islands by their Chinese name on Aug. 28, prompting Japan to file diplomatic protests. Three other countries protested similar claims.

“Diaoyu Dao and its affiliated islands have all along been China’s territory,” Ning said. “It is only natural that they are marked as Chinese territory on a map. China does not accept Japan’s protest.”

The Senkakus – about 2 ½ square miles – have been a flashpoint ever since China claimed the islands in 1992 and began sending government ships there 16 years later, according to Japan’s Ministry of Foreign Affairs’ website.

The islands, said to contain a wealth of natural resources, including fish, oil and natural gas, are the scene of near-daily exchanges between the two nations’ coast guards. China sends its vessels into waters claimed by Japan to intimidate Japanese fishing boats, which Japan’s coast guard are on hand to shield.

The most recent row began Aug. 28 when China’s Ministry of Natural Resources released its 2023 standard map, the state-affiliated China Daily reported that day. The annually updated standard map shows the communist nation’s shifting territorial claims.

Afterward, Japan’s Ministry of Foreign Affairs complained to the Chinese Embassy in Tokyo and to the Chinese government in Beijing, a ministry spokesman said by phone Thursday. He declined to say when the protests occurred.

Some government officials in Japan are required to speak to the media only on condition of anonymity.

The ministry demanded an immediate retraction, Japanese Chief Cabinet Secretary Hirokazu Matsuno told reporters Tuesday, according to video of his press conference in Tokyo.

“We are keeping a concerned eye on this move made by China,” he said. “The Senkakus are unquestionably an inherent part of Japan’s territory, in terms of both history and international law.”

Matsuno said the ministry would uphold Japanese sovereignty “calmly and with a resolute attitude.” The Philippines, Vietnam and Malaysia also protested China’s claims, Japanese public broadcaster NHK said Wednesday.

Chinese coast guard vessels have entered the 12-mile territorial limit around the Senkakus 22 times this year, with the last incident occurring Aug. 23, a Japan coast guard spokesman said by phone Thursday.