SINGAPORE — Although Defense Secretary Jim Mattis is expected to discuss North Korea during his talks with allies and partners at an annual defense conference in Singapore, he is also expected to address the other 800-lb. gorilla in the room — China.

During a speech at the annual Shangri La Dialogue, a yearly gathering of officials and experts, Mattis is expected to call out China for its misbehavior in the South China Sea.

Within the last month, China deployed anti-ship missiles, surface-to-air missile systems, and electronic jammers to land features in the South China Sea which are also claimed by Brunei, Taiwan, Malaysia, Indonesia, the Philippines and Vietnam.

China deployed these weapons to the land features, despite promising in 2015 in the White House Rose Garden that it would not “militarize” them. China also recently landed a bomber on one of the islands.

In response, the Pentagon last week disinvited China from the Rim of the Pacific (RIMPAC), the world’s largest multinational naval military exercises, led by the U.S. Navy. The U.S. first invited China to participate in 2014, as a gesture of good will and growing cooperation between their two militaries.

The Pentagon then sent two warships through the South China Sea as part of what is called a “freedom of navigation operation” to ensure that the waterway remains open for international commerce despite territorial claims.

On Thursday, Mattis announced he was renaming Pacific Command, the U.S. military’s command over the Asia Pacific region to “Indo-Pacific Command.” The name change is a reflection of the U.S.’s growing relationship with India as an ally against China and the Indian Ocean as a strategic region.

Speaking moments after Mattis, former Pacom commander Adm. Harry Harris — who is nominated to become the next U.S. Ambassador to South Korea — said the U.S. must “stand ready to confront” China when necessary.

“Without focused involvement and engagement by the United States and our allies and partners, China will realize its dream of hegemony in Asia. We should cooperate with Beijing where we can, but stand ready to confront them when we must,” he said.

“Great power competition is back,” he added.

Meanwhile, back in the U.S., the Director of the Joint Chiefs of Staff, Marine Lt. Gen. Kenneth McKenzie said in response to a question about those militarized land features that the U.S. military “has had a lot of experience” in the Western Pacific “taking down small islands.”

“I would just tell you that the United States military has had a lot of experience in the Western Pacific, taking down small islands,” he said, before later clarifying he was just stating a fact.

Exactly how far Mattis will go in his speech on China on Saturday remains to be seen. In recent days, he has addressed China’s behavior but not named it specifically.

On Wednesday he said the U.S. would confront behavior “out of step” with international law in response to a question about China’s deployment of missiles in the South China Sea.

The next day, he also took a veiled swipe at China’s “One Belt One Road” initiative, which funds infrastructure projects all throughout Asia and Africa that could potentially later serve as military bases.

“The Indo-Pacific has many belts and many roads,” he said.

Mattis’ speech will be closely watched at the conference, which is being attended by officials from about 40 countries, including China. It will come after a speech Friday night by Indian Prime Minister Narendra Modi that emphasized the need for cooperation in the region, including between India and China.

Some China experts say they welcome a tougher stance against China.

Bonnie Glaser, senior adviser for Asia and director of the China Power Project at the Center for Strategic and International Studies (CSIS) said China has harassed the Philippines’ resupply operation at Second Thomas Shoal, threatened Vietnam and the Philippines with consequences if they drill for energy inside their own exclusive economic zones and continental shelves that are rightfully theirs; and militarized outposts in the South China Sea.

“Secretary Mattis should call out China for its recent actions,” she said.