A Chinese commander, sitting alongside a fellow military leader from the United States and another one from Japan, defiantly said China owns the South China Sea at a conference in London.

“The South China Sea, as the name indicated, is a sea area. It belongs to China,” said Vice Adm. Yuan Yubai, commander of the North Sea Fleet for the People’s Liberation Army Navy, Defense One reports.

For the three military leaders to appear together was a rare occurrence, notes the report. All three have different views on maritime security in the South China Sea region.

The audience attended the conference in London to lend an ear to a discussion about the contentious South China Sea.

Although political theater did make an appearance accompanied by a few one-liners, cordiality reportedly prevailed and the admirals actually traded smiles and shook hands before and after.

The Chinese admiral pointed out that his country and the United States are crafting a code of conduct for aircraft encounters, which he hoped would prevent disputes among the five countries with territory claims in the South China Sea.

“I believe after this code of conduct is successfully passed, all the neighboring countries around this area will have good communication with each other whenever such unexpected encounters occur,” reportedly said Yuan.

The three military leaders came together at the Defense & Security Equipment International (DSEI) conference in London which hosts naval leaders from across the globe.

Siting next to Yuan were U.S. Navy Rear Adm. Jeff Harley, assistant deputy chief of naval operations for operations, plans and strategy, and Vice Adm. Umio Otsuka, president of the Japanese Maritime Self-Defense Force Command and Staff College.

In late May, U.S. Secretary of Defense Ashton Carter declared that the United States would not be deterred by China’s military activity in the Asia-Pacific region, criticizing Beijing’s artificial island construction in the South China Sea.

Speaking at the Shangri-La Dialogue in Singapore, the Pentagon chief stressed that America will remain the leading security power in the Pacific for many years to come.

China has been building thousands of acres of artificial islands, airstrips, hangars, and ship berths in the South China Sea, an estimated 660 miles from its shores—a move that has ignited territorial disputes with other countries in the region.

Beijing has repeatedly defended its rights and interests to create the new land.

“I want to reaffirm that this construction is well within the scope of China’s sovereignty and it is justified, legitimate and reasonable,” said Chinese Adm. Sun Jianguo, the deputy chief of General Staff Department of the People’s Liberation Army, at the Shangri-La Dialogue in Singapore a day after the U.S. defense secretary spoke there.

When addressing the conference in London, Adm. Yubai touched on maritime trade and commerce as well as Chinese President Xi Jinping’s idea of building ports along global trade routes.

“But the real point of interest was the South China Sea, where U.S. and Japan have protested China’s island-building,” notes Defense One. “U.S. Adm. Harry Harris, Pacific Command commander, has said the islands are clearly intended for military use as forward operating bases.”

“China has been rapidly building a giant airstrip Fiery Cross Reef. The U.S. Navy has released video of the islands by a P-8 spy plane,” it adds. “The Navy also released audio radio calls of the Chinese Navy telling the American plane to get lost.”

Yuan suggested that joint efforts and negotiations involving the countries in the South China Sea region could solve the land claim disputes.

In May, the U.S. defense chief pointed out that China’s activity in the South China Sea threatens the security of the region, adding that other land claimants were also at fault.

Secretary Carter urged a peaceful resolution to the land reclamation friction, asserting that the United States is opposed to the “militarization of disputed features.”

“There should be an immediate and lasting halt to land reclamation by all claimants,” the secretary said, later adding, “There should be no mistake: the United States will fly, sail, and operate wherever international law allows, as U.S. forces do all over the world. America, alongside its allies and partners in the regional architecture, will not be deterred from exercising these rights – the rights of all nations.”