The visit is the third by an American military vessel to the former Saigon since the 1975 end of the Vietnam War, and the fourth overall to Vietnam.

But it marks the first time that two US ships have visited the communist country at the same time.

The event is part of efforts to ease lingering distrust between the militaries of the two former foes following the war, during which more than 58,000 Americans and about three million Vietnamese died.

"Relations between the two countries are now normalised and this visit contributes to reinforce relations, especially regarding regional security issues and anti-terrorism," said Vietnamese navy Colonel Dang Thuc Hoa.