The U.S. Defense Department disinvited China from the forthcoming Rim of the Pacific (RIMPAC) exercise due to militarization in the South China Sea and the Spratly Islands in particular, a department spokesperson said on Thursday.

Marine Lt. Col. Christopher Logan said China’s “continued militarization of the South China Sea” is “inconsistent with the principles and purposes of the RIMPAC exercise.”

The People's Liberation Army (Navy) hospital ship Peace Ark (T-AH 866), the U.S. Navy hospital ship USNS Mercy (T-AH 19), the Military Sealift Command fast combat support ship  USNS Rainier (T-AOE 7) and the Royal Norwegian Navy frigate HNoMS Fridtjof Nansen (F310) maneuver into formation for a photo exercise during Rim of the Pacific (RIMPAC) 2014. (U.S. Navy photo)
The People’s Liberation Army (Navy) hospital ship Peace Ark (T-AH 866), the U.S. Navy hospital ship USNS Mercy (T-AH 19), the Military Sealift Command fast combat support ship USNS Rainier (T-AOE 7) and the Royal Norwegian Navy frigate HNoMS Fridtjof Nansen (F310) maneuver into formation for a photo exercise during Rim of the Pacific (RIMPAC) 2014. (U.S. Navy photo)

The U.S. first invited the People’s Liberation Army Navy (PLAN) to the 2014 RIMPAC and again invited them to the 2016 exercise.

RIMPAC occurs every two years from June to July and involves dozens of ships, hundreds of aircraft, and thousands of personnel conducting operations near Hawaii. It is meant to help participants build and maintain cooperative relationships at sea.

 Logan said “we have strong evidence that China has deployed anti-ship missiles, surface-to-air missiles (SAM) systems, and electronic jammers to contested features in the Spratly Islands region in the South China Sea. China’s landing of a bomber aircraft at Woody Island has also raised tensions.”

Although China has said it is building on the islands for positive effects like safety at sea, navigation assistance, search and resuce, fisheries protection, and other non-military purposes, “the placement of these weapon systems is only for military use,” Logan said.

Logan noted that while the U.S. is committed to an open Indo-Pacific region, China’s militarization of these features “only serve to raise tensions and destabilize the region.” The disinvitation is an “initial response” to the militarization.

He added the U.S. has called on China to remove the military systems immediately and stop militarizing disputed South China Sea areas.

“We believe these recent deployments and the continued militarization of these features is a violation of the promise that President Xi made to the United States and the World not to militarize the Spratly Islands,” Logan said.

In 2016 China sent five ships, three helicopters, a marine squad, and over a thousand total personnel to the RIMPAC. This included the missile destroyer Xi’an, missile frigate Hengshui, supply ship Gaoyouhu, hospital ship Peace Ark, and submarine rescue vessel Changdao.

Russia participated in the 2012 RIMPAC but declined to participate in 2014 and was disinvited in 2016 due to its annexation of Ukraine’s Crimean peninsula.