The USS Ronald Reagan's port call in Danang comes as the United States and Vietnam celebrate the 10th anniversary of their "comprehensive partnership".

The aircraft carrier – part of the US 7^th Fleet "supporting a free and open Indo-Pacific region" – arrived with two escort ships, the guided-missile cruisers USS Antietam and USS Robert Smalls, the American Embassy in Hanoi said.

US Navy officials disembarked and shook hands with their Vietnamese military counterparts in a brief ceremony on Sunday afternoon.

"More than 5,000 sailors aboard USS Ronald Reagan are eager to visit Danang and experience Vietnamese culture," USS Ronald Reagan's commanding officer Captain Daryle Cardone said in a statement.

Vietnam and the US share increasingly close trade links, as well as concerns over China's growing strength in the region.

A Chinese survey vessel, multiple coast guard ships and fishing boats operated for several weeks in Vietnam's exclusive economic zone in the South China Sea, prompting a demand that they leave from Vietnam's foreign ministry.

The boats eventually departed in early June.

China claims most of the resource-rich waterway despite competing claims from other Southeast Asian nations including Vietnam, the Philippines and Malaysia.

"The visit gives that message that Vietnam is continuing to balance against China by improving its security relationship with the US, and with other outside powers," Nguyen The Phuong, a PhD candidate in maritime security at the University of New South Wales Canberra, told AFP.

Bilateral ties

The US aircraft carrier's visit follows the arrival of Indian naval ships in Danang last month, as well as a port call by Japan's largest warship in Cam Ranh, a city on the southeastern coast, earlier this week.

Pham Thu Hang, spokesperson for Vietnam's foreign ministry, said earlier in the week that port calls were an "ordinary friendship exchange for peace, stability and cooperation and development in the region and the world".

Strong bilateral ties between the US and Vietnam are key for Washington if it wants to remain the dominant power in the region, Phuong said.

"The US hopes that by sending one of their most formidable naval assets, they will have a trusted and reliable partner in Vietnam," he said.

The US Secretary of State Antony Blinken made a quick visit to Hanoi in April and made it clear he wanted to upgrade diplomatic ties.

This is the third visit by a US aircraft carrier to Vietnam after a historic port call by the USS Carl Vinson in 2018, the first time such a ship had arrived in the country since the end of the war.

The visit includes several cultural and community events, such as a US Navy band concert, a visit to an orphanage and sports matches. 

The USS Ronald Reagan has been based in Japan since 2015.