(Reuters) -- U.S. Defense Secretary Lloyd Austin met Cambodia's leadership on Tuesday and discussed resuming military training programs, in a visit aimed at reversing gains made by China amid concern about its growing presence at a Cambodian naval base.
Cambodia allowing China to develop Ream Naval Base, located at a key waterway to the Gulf of Thailand in Sihanoukville province, has Washington worried that it will give Beijing a new outpost near the contested South China Sea, much of which is claimed by China.
Ties between the United States and Cambodia have been strained in recent years, with Washington vocal over the government's dismantling of the political opposition and concerned about China's growing influence.
Austin held separate meetings with Cambodian Prime Minister Hun Manet and the leader's father Hun Sen, who until last year had been premier for nearly four decades and now serves as president of the senate. He also met with Defense Minister Tea Seiha.
"We had substantive conversations about ways to strengthen U.S.-Cambodian defense ties, and I'm looking forward to further dialogue," Austin said of the meetings, in a post on social media platform X.
Cambodian media carried pictures from the meetings but the government had yet to issue a statement on the outcome.
There has been some U.S. optimism that Hun Manet, who studied economics at New York University and attended the U.S. military academy at West Point, would be more aligned with Washington than his father Hun Sen.
Self-styled "strongman" Hun Sen has said his son would rule in his own model. Hun Sen gained a reputation for his open defiance of the United States during a sweeping, yearslong crackdown that saw opposition parties banned and scores of politicians jailed in absentia for treason and incitement.
He had championed close relations with China, which has sought to influence Cambodia's position within the regional bloc ASEAN, which makes decisions based on consensus.
Pentagon spokesperson Major General Patrick Ryder said Austin's discussions included resuming military training exchanges on disaster assistance and U.N. peacekeeping, as well demining and unexploded ordnance clearance.
Ryder said Austin engaged with Cambodian alumni of U.S. military education programs and U.S. military academy cadets who were visiting Cambodia.
China has been boosting its "ironclad" friendship with the Southeast Asian country, amid high-level state and military leader exchanges since last year.
Before a China-funded upgrade began in June 2022, the Ream base had been the site of some joint naval training and exercises between the United States and Cambodia. Cambodia demolished the U.S.-built facility in October 2020.
Two Chinese warships, likely corvettes or frigates, have been docked at Ream since December. Adding to the U.S. concerns, China last month sent two warships to Cambodia and East Timor on a tour that will last to mid-June.
Last week, Hun Manet said Cambodia would begin construction in August of a Chinese-backed $1.7 billion canal that has caused tension with neighboring Vietnam and sparked fears that it could be used by Chinese warships. Cambodia has dismissed those claims as baseless.