WASHINGTON, Aug 30 (Reuters) - U.S. national security adviser Jake Sullivan will meet with his Japanese and South Korean counterparts on Wednesday and Thursday in Hawaii, the White House said, amid heightened tensions in the region between China and Taiwan.

"After the trilateral meeting, Mr. Sullivan will visit the United States Indo-Pacific Command to discuss our alliances in defense of the free and open Indo-Pacific," National Security Council spokesperson Adrienne Watson said in a statement.

Two U.S. Navy warships sailed through international waters in the Taiwan Strait on Sunday, the first such operation since a visit to Taiwan by U.S. House Speaker Nancy Pelosi enraged China, which regards the island as its territory.

The operation demonstrates the United States' commitment to a free and open Indo-Pacific, and the U.S. military flies, sails and operates anywhere international law allows, the Navy said at the time.

The narrow Taiwan Strait has been a frequent source of military tension since the defeated Republic of China government fled to Taiwan in 1949 after losing a civil war with the communists, who established the People's Republic of China.

National Security Secretariat Secretary General Akiba Takeo of Japan, and South Korea's Director of the National Security Office Kim Sung-han will meet with Sullivan at the headquarters of the United States Indo-Pacific Command in Honolulu, according to Tuesday's statement.