The Pentagon has “disinvited” the Chinese navy from participating in the world’s largest annual maritime military exercise in the Pacific, citing what U.S. officials say is Beijing’s continued militarization of territories and the sea lanes in the hotly contested South China Sea.

Chinese forces have joined the U.S. and 27 other countries in the Rim of the Pacific, or “RIMPAC,” exercises since 2014 in an effort to bolster military ties between Beijing and Washington, and China’s military earlier this year said it was anticipating another invitation for 2018. Top officials in both Beijing and Washington have touted the drills as a vital bridge to future military cooperation and easing tensions in the Pacific.

But China’s aggressive moves to deploy advanced weaponry onto man-made islands in disputed areas of the South China Sea, despite protests from the U.S. and its allies in the region, prompted Washington to take action.

“China’s continued militarization of disputed features in the South China Sea only serve to raise tensions and destabilize the region [and] … we have disinvited the [Chinese] Navy from the 2018 Rim of the Pacific Exercise,” Pentagon spokesman Lt. Col. Christopher Logan said in a statement Wednesday.

Chinese officials immediately slammed the move, which comes amid bilateral tensions over trade and the fate of U.S. negotiations with North Korea — negotiations in which Beijing is expected to have a major influence. Chinese officials said the RIMPAC cancellation was another example of the “negative mindset” by some in the Trump administration to the prospect of better bilateral relations.

Chinese Foreign Minister Wang Yi called the move as “nonconstructive” and “unhelpful to mutual understanding” between Washington and Beijing. His comments came after a closed-door meeting with Secretary of State Mike Pompeo in Washington on Wednesday.

Mr. Wang called China’s deployments as necessary defense of its sovereign territory, likening China’s South China Sea outposts to the U.S. military presence in Hawaii and Guam.

RIMPAC began in 1971 and was held annually until 1974, when it switched to every two years due to its large scale. The founding nations are the United States, Australia and Canada.

China has participated twice previously, in 2014 and 2016, both times under President Obama.

China’s participation in the exercises has sparked controversy before. During the 2014 exercises, China deployed a Type 815 Dongdiao-class spy ship to monitor communications between the U.S. and international vessels. The spy ship was not on the official docket of participating vessels during that year’s exercises, and spent the majority of its time stationed in international waters off the coast of Hawaii.

China’s recent deployments of anti-ship weapons, surface-to-air missiles and electronic jamming equipment to areas near the Spratly Islands, and the arrival of long-range bombers to a Chinese air base on Woody Island are clear signs of Beijing’s intent to lay claim to the South China Sea through military might,” Col. Logan argued.

He called the moves “a violation of the promise that [Chinese President Xi Jinping] made to the United States and the world not to militarize the Spratly Islands” he added.

Mr. Wang said the South China Sea build-up was necessary to defend Beijing’s authority over what it considers its sovereign territory within the disputed waters.

Several lawmakers on Capitol Hill applauded the Pentagon’s decision to disinvite Beijing.

“China views its RIMPAC participation as a sign of its international legitimacy,” tweeted Rep. Mike Gallagher, Wisconsin Republican. “This move sends a strong signal to the [Chinese] leadership that its reckless behavior in the South China Sea carries with it real consequences.”

But private analysts said the RIMPAC move was a symbolic one that may have little practical effect on China’s growing hold on the waters off its vast Pacific coastline.

“It doesn’t really do anything to deter China in the South China Sea,” said Gregory Poling, an Asia expert at the Center for Strategic and International Studies. “So this is really more about venting our frustration and sending a signal than it is actually trying to change Chinese behavior.”