The Chinese defense chief warned the United States on Monday against provoking military tensions by "flexing muscles" in the contested South China Sea, while his American counterpart urged claimant nations to use their sovereign spaces "or risk losing them."

During a 30-minute meeting in Bangkok with U.S. Defense Secretary Mark Esper, Chinese Defense Minister Gen. Wei Fenghe underscored Beijing's "commitment to safeguarding territorial sovereignty and maritime rights" in the disputed sea, a spokesman for Wei told reporters.

"The Chinese side also urged the United States to stop flexing muscles in the South China Sea, and to not provoke and escalate tensions," Col. Wu Qian, spokesman for China's Ministry of National Defense, said through an interpreter. "We called [on the United States] to stop intervening in the South China Sea and stop military provocation."

Wei's comments came as Beijing's first domestically-built aircraft carrier headed into the South China Sea from the Taiwan Strait as part of "equipment tests and routine training," according to the state-run Xinhua News Agency.

China claims almost all of the sea, a vital waterway for international shipping and trade, while Brunei, Malaysia, the Philippines, Vietnam and Taiwan have their own overlapping claims to portions of the disputed waters.

On Sunday, Esper urged claimant nations to protect their sovereign waters especially.

"I encourage you to use your sovereign spaces, as well as international ones, or risk losing them," he said.

"Together, we must stand for lawful uses of air and maritime spaces to push back against coercion and intimidation," the American defense secretary said, as he criticized Beijing's for stepping up the use of what it calls "maritime militia vessels" in the South China Sea.

Up to 95 Chinese militia ships had been monitored on Dec. 20 last year in an area near Chinese-occupied Subi Reef, according to a report published by the Asia Maritime Transparency Initiative (AMTI), a U.S.-based think-tank.

Beijing has strengthened its presence in the maritime region by expanding shoals into artificial islands and building military and other facilities.

"China's activities there are a threat not only to other claimants and the many Southeast Asian nations, but to all trading nations who value freedom of the seas, and the peaceful settlement of disputes," Esper said.

Esper made the comments during a speech at a ceremony in which the United States and Thailand reaffirmed their defense alliance. He met with his Chinese counterpart the next day on the sidelines of a conference of defense ministers from the 10-member Association of Southeast Asian Nations (ASEAN) and eight other dialogue partners, including China and the United States.

For nearly two decades, China and ASEAN have been negotiating a code of conduct to regulate behavior in the South China Sea. Washington, in the meantime, has pressed ahead with freedom of navigation flights and sailing in the sea, through which about U.S. $5 trillion in ship-borne trade passes annually.

Esper said the United States had conducted "more freedom of navigation operations in the South China Sea, in 2019, than in any of the past 25 years."

"These operations are intended to demonstrate that the United States will continue to fly, to sail and operate wherever international law allows," he said. "This has been particularly important in responding to steps Beijing has taken to militarize outposts in the South China Sea."

Esper said China, through its militia ships, had "tried to strong arm" and intimidate its smaller Asian neighbors from drilling for oil and natural gas reserves off their own shores.

The U.S. Navy regularly conducts what it calls "freedom of navigation" operations by ships close to some of the islands China occupies.

The Chinese navy said in a statement that the U.S. Navy destroyer USS Wayne E. Meyer had "trespassed" into the adjacent waters off the Nansha Islands on Aug. 28 without permission of the Chinese government.

It said Washington's action had "seriously endangered the peace and stability in the South China Sea." "Nansha" is the Chinese name for the contested Spratly islands.

Taiwan scrambles jets

In related developments, Taiwan, a self-governing island claimed by China, said it had scrambled jets and ships on Sunday to monitor the southbound Chinese warships led by the aircraft carrier, which has yet to be named.

On Monday, Chinese navy spokesman Cheng Dewei said on his social media account that the carrier's voyage in the South China Sea was "normal practice."

"This is not aimed towards any specific target, and has no relation to the current situation," Cheng said.

A Chinese aircraft carrier had also passed through the Taiwan Strait in June, Taipei's defense ministry said in a statement.

Meanwhile, according to Malaysian Defense Minister Mohamad Sabu, China and the ASEAN bloc had agreed in principle to take part in another joint naval drill.

"We have agreed to conduct the second maritime exercise. However, we did not discuss in detail when and where it will be held," Malaysia's state news agency, Bernama, quoted Mohamad Sabu as telling reporters.

ASEAN and China conducted their first naval drills at the Zhanjiang Naval Base in southern China in October 2018.

ASEAN defense chiefs, during their meeting in Bangkok, also agreed that a code of conduct in the South China Sea "should be done soonest to increase stability," Gen. Raksak Rojpimpan, the Thai defense ministry's director of policy and planning, told reporters here on Monday.

"Thailand's policy is to strike the balance, we cannot choose sides," he said. "It is just a small country, we balance it out and befriend every country."

Reported by BenarNews, an RFA-affiliated online news service.

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