U.S. Pacific Fleet commander Adm. Scott Swift speaks to reporters Tuesday, July 5, 2016, at Joint Base Pearl Harbor-Hickam, Hawaii, for the kickoff of the Rim of the Pacific exercise in Hawaii and California. (Wyatt Olson/Stars and Stripes)

JOINT BASE PEARL HARBOR-HICKAM, Hawaii — The hot topic for the Rim of the Pacific remains unchanged from the last version of the maritime exercise in 2014: China.

This marks the second time China has been a full participant in RIMPAC, bringing five ships compared with two in 2014, and the country will play a much larger role.

During a Tuesday news conference kicking off the six-week exercise — the largest so far — Pacific Fleet commander Adm. Scott Swift was flanked by top commanders from many of the 26 participating nations. Beside him was Vice Adm. Nora Tyson, commander of the U.S. Third Fleet, who is heading the exercise’s combined task force.

Swift’s opening remarks didn’t mention China by name, but his first talking point echoed repeated calls by U.S. civilian and military officials to maintain the U.S.-led status quo in the Pacific region in response to ever-greater Chinese military might.

“[RIMPAC] brings together 26 nations from North and South America, Europe, Asia and Oceania,” Swift said. “This is what the international maritime community does in ensuring the norms, standards, rules and laws that have provided the great stability and security — the foundation for prosperity — that we’ve all enjoyed over the last 70 years.”

The biennial exercise is “a recurring answer to the divisive angst and tensions that put security and stability at risk in this region,” he said.

“Protecting and navigating these shared interests increasingly rests on the hulls of our ships, the wings of our aircraft and on the backs of every mariner represented here at RIMPAC,” Swift said, adding that the exercise was a time for all participants to “set their differences aside.”

Some U.S. lawmakers had called on the Pacific Fleet to disinvite China because of its actions in the South China Sea, where it has dredged sand to build up tiny islands and reefs. The country has added facilities and runways on those islands, which are in waters claimed by other countries, most notably the Philippines.

“I think it’s great that China is here and a part of this enterprise,” Tyson told reporters after the news conference. “I think every country is a valuable participant for RIMPAC.”

Most of the questions asked of Swift and Tyson were about China. Swift was asked about whether Beijing had been unduly “rewarded” with participation in RIMPAC, given it is challenging U.S. naval dominance in parts of the South China Sea.

“My first response is that RIMPAC is not about China,” Swift said. China is a “significant country,” just as are others with advanced armed forces, such as Australia and Japan, he said.

Pacific Fleet staff have a prescribed selection process for vetting which nations get invited and in what drills they will participate, which has “nothing to do with rewarding anyone or diminishing anyone,” Swift said.

He said China is playing an “increased role” in this year’s RIMPAC.

As it did in 2014, China sent the hospital ship Peace Ark, along with the guided missile destroy Xian, guided-missile frigate Hengshui, fleet oiler Gaoyouhui and the submarine logistics vessel Changxingdao.

China will participate in a new submarine rescue scenario, among other drills.

“For any country that has submarines, submarine rescue is very important,” Tyson told reporters. “I think it’s great we’re bringing these submarine rescue capabilities together so that we understand what is available in case we have an emergency with a submarine. There is a global system that will respond if any of us were to have an emergency with a submarine.”

Also new for this year’s exercise is a littoral combat ship firing a Harpoon missile at a retired U.S. frigate and amphibious operations taking place in Southern California and Hawaii.

As part of the Navy’s renewable-energy “Great Green Fleet,” all participating surface vessels at RIMPAC will use biofuel.

RIMPAC participants include Australia, Brunei, Canada, Chile, China, Colombia, Denmark, France, Germany, India, Indonesia, Italy, Japan, Malaysia, Mexico, Netherlands, New Zealand, Norway, Peru, South Korea, Philippines, Singapore, Thailand, Tonga, the United Kingdom and the United States. Denmark, Italy and Germany are participating for the first time.

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U.S. Pacific Fleet commander Adm. Scott Swift speaks to reporters Tuesday, July 5, 2016, at Joint Base Pearl Harbor-Hickam, Hawaii, for the kickoff of the Rim of the Pacific exercise in Hawaii and California. (Wyatt Olson/Stars and Stripes)

Navy Vice Adm. Nora Tyson, commander of the U.S. Third Fleet, is leading the combined task force for Rim of the Pacific exercises this year. She told reporters Tuesday, July 5, 2016, that she welcomed greater participation by China in the biennial drills underway in Hawaii and Southern California. (Wyatt Olson/Stars and Stripes)