A China coast guard ship formation passed through the waters of the Senkaku Islands on Sunday on a "rights enforcement patrol," the coast guard said in a statement, as Beijing ramps up tensions with Japan over its prime minister's remarks about Taiwan.
A diplomatic spat between China and Japan has intensified since Japanese Prime Minister Sanae Takaichi told parliament on Nov. 7 that a hypothetical Chinese attack on democratically ruled Taiwan could trigger a military response from Tokyo.
The remarks sparked an angry response from Beijing, which has signaled that it expects Takaichi to retract them in some fashion.
China claims Taiwan as its own territory and has not ruled out the use of force to take control of the island, which is just 68 miles from Japanese territory. Taiwan's government rejects Beijing's sovereignty claims.
"China Coast Guard vessel 1307 formation conducted patrols within the territorial waters of the Diaoyu Islands. This was a lawful patrol operation conducted by the China Coast Guard to uphold its rights and interests," the statement said.
China and Japan have repeatedly faced off around the Japan-administered islands, which Beijing calls Diaoyu and Tokyo calls the Senkaku.
The Japanese Embassy in Beijing did not immediately respond to a request for comment.
Japan has been facing mounting pressure from China since Takaichi made her remarks, with China's consul general in Osaka commenting: "The dirty head that sticks itself out must be cut off," prompting a formal protest from Tokyo.
Beijing then summoned the Japanese ambassador for the first time in more than two years, and China's defense ministry declared that any Japanese intervention would be doomed to fail.
On Friday, China cautioned its citizens against traveling to Japan, prompting Tokyo to urge Beijing to take "appropriate measures," though it did not elaborate.
Three Chinese airlines said on Saturday that tickets to Japan could be refunded or changed for free.
In Taiwan, the defense ministry said Sunday morning it had detected 30 Chinese military aircraft operating around the island and seven navy ships over the previous 24 hours.
Late Saturday, the ministry said China had been carrying out another "joint combat patrol" to "harass the air space and sea around us." It added Taiwan had sent its own aircraft and ships to monitor the situation. Taiwan reports such Chinese patrols a couple of times a month as part of what Taipei says is an ongoing military pressure campaign.
Taiwan's government says only the island's people can decide its future.
Japanese leaders have previously avoided publicly mentioning Taiwan in discussing such scenarios, maintaining a "strategic ambiguity" also favored by Tokyo's main security ally, the United States.
