The U.S. military brushed off complaints from China over sending U.S. aircraft to fly over the Taiwan Strait on Tuesday.
China has long claimed sovereignty over Taiwan and the Taiwan Strait, the relatively narrow strip of ocean between the island of Taiwan and the Chinese mainland. The Chinese military has frequently sent planes into the area, testing Taiwan's air defense zone.
The U.S. sent a P8-A anti-submarine aircraft into the strait on Friday, leading China to send its own planes, Reuters reported.
"U.S Navy vessels and aircraft routinely interact with foreign warships and aircraft while operating throughout the region," the U.S. Indo-Pacific Command said in a Tuesday statement.
"All interactions with foreign military forces during the transit were consistent with international norms and did not impact the operation," it continued. "The United States will continue to fly, sail and operate anywhere international law allows including within the Taiwan Strait. The aircraft's transit of the Taiwan Strait demonstrates the United States' commitment to a free and open Indo-Pacific."
The testy exchange comes as both China and North Korea are accusing the U.S. of attempting to create an "Asia-style NATO."
The North Korean government cited military cooperation between the U.S. and allies in Japan and South Korea in a statement on Monday.
"While blatantly holding joint military exercises with Japan and South Korea, the United States is making a full-fledged move to establish an Asia-style NATO," North Korea's foreign ministry wrote.
The regime's complaints echo China's condemnation of the newly revitalized Quad alliance, which includes the U.S., Japan, India and Australia.
President Joe Biden's administration has ramped up military cooperation with Asian allies as China has grown increasingly aggressive toward Taiwan and North Korea nears a potential nuclear test.
China condemned the Quad alliance as an attempt to form an "Asian NATO" earlier this year. Unlike NATO, however, Quad members-only agree to cooperate economically and do not sign a mutual defense pact.