American and Canadian warships sailed through the Taiwan Strait on Tuesday, in the first military freedom of navigation operation since U.S. President Joe Biden said the U.S. would defend Taiwan if it were attacked by China. USS Higgins, a U.S. Navy guided-missile destroyer, and HMCS Vancouver, a Royal Canadian Navy frigate, conducted “a routine Taiwan Strait transit on September 20 through waters where high seas freedoms of navigation and overflight apply in accordance with international law,” Pentagon press secretary Brig. Gen. Pat Ryder told reporters Tuesday. China has claimed the Taiwan Strait is not international waters, but “are China's internal waters” and “territorial sea.” However, under international law, the Taiwan Strait contains a corridor of international waters and airspace beyond the territorial sea of any state where all vessels can navigate freely. “Higgins’ and Vancouver’s transit through the Taiwan Strait demonstrates the commitment of the United States and our allies and partners to a free and open Indo-Pacific,” added a statement from U.S. Seventh Fleet, which covers U.S. military naval operations in the eastern Pacific and Indian Oceans. The strait separates Taiwan, a democratic self-ruled island, from mainland China. Beijing claims sovereignty over Taiwan and its surrounding waters despite the Chinese Communist Party never controlling the island. The transit comes shortly after CBS "60 Minutes" aired an interview with President Biden in which he said U.S. troops would defend the island from attack. The U.S. president had pledged to defend Taiwan before, but he added in this interview that “U.S. men and women” would be part of that defense. Prior to his statement, U.S. policy has remained intentionally ambiguous as to how the U.S. would defend Taiwan if the democratic island were to come under attack from China. Tuesday's transit marked the second time a U.S. Navy warship had made the voyage in the Taiwan Strait since Democratic House Speaker Nancy Pelosi visited the island. USS Antietam and USS Chancellorsville sailed through the strait in late August. Tensions between Beijing and Taipei are high, with the Chinese military holding large military drills near the island.