A U.S. Navy destroyer sailed within 12 miles of a disputed Chinese manmade island in the South China Sea on Wednesday, the first such challenge to a Chinese maritime claim to take place under the Trump administration.

According to a U.S. official, the destroyer USS Dewey sailed within 12 miles of Mischief Reef on Wednesday conducting a Freedom of Navigation Operation (FONOP), said a U.S. official. The reef is one of seven artificial islands in the Spratly Islands that China has claimed as its territory after building up reefs that at times had previously been under water.

In recent years China dredged massive amounts of sand and earth to build up the reefs into artificial islands that now include airfields and other facilities that could be used by China’s military.

The U.S. military’s freedom of navigation operations challenge excessive maritime claims made by countries worldwide by sailing within the 12 mile territorial limits that extend from shore.

Wednesday’s freedom of navigation operation operation near Mischief Reef was first reported by the Wall Street Journal.

The move is sure to antagonize China, which has reacted negatively to previous freedom of navigation operations in the Spratly Islands and Paracel Islands, two island chains in the South China Sea. The last time the U.S. military conducted such an operation near a disputed island in the South China Sea was in October under the Trump administration.

Without confirming Wednesday’s freedom of navigation operation, Captain Jeff Davis, a Pentagon spokesman said, “We operate in the Asia-Pacific region on a daily basis, including in the South China Sea. We operate in accordance with international law.”

“We fly, sail, and operate wherever international law allows,” added Davis. “We have a comprehensive Freedom of Navigation Operations program that seeks to challenge excessive maritime claims in order to preserve the rights, freedoms, and uses of the sea and airspace guaranteed to all nations under international law.:

He added that the operations are not directed at any one country or specific bodies of water. In 2016 the United States conducted challenged the excessive maritime claims of 22 countries including allies and partners.

“We are continuing regular FONOPS, as we have routinely done in the past and will continue to do in the future,” said Davis.