The USS Curtis Wilbur, an Arleigh Burke class guided missile destroyer, pulled into the Tien Sa Port where it was met by the US Ambassador to Vietnam, Raymond Burghardt, and officers from the regional Vietnamese Navy command.

The ship, which is part of the US Pacific Fleet based in Yokosuka, Japan, will spend six days in Danang, the city where US Marines landed in March 1965, becoming the first American combat troops in Vietnam.

Previously, US military personnel, who had been in the country since 1955, were only authorised to act as advisors to the South Vietnamese army and not participate in fighting communist forces.

The amphibious arrival of the Marines in Danang, which became a major US military base, marked the start of the "Americanisation" of the war.

An American and a Vietnamese flag hung side-by-side on board the ship, flapping gently in the breeze, while the crew, dressed in white uniforms, manned the rails as part of traditional US Navy protocol for coming into port.

The visit is part of efforts to ease the mutual distrust between the militaries of the two nations as a result of the Vietnam War, during which more than 58,000 Americans and about three million Vietnamese died.

Military-to-military relations still remain largely confined to joint search operations for US servicemen missing in action from the war.

Before the USS Curtis Wilbur departs on Monday, representatives of the ship's some 300 crew will visit a local school and an orphanage, and also play volleyball against a Vietnamese Navy team.

In an unofficial capacity, many are also expected to make a pilgrimage to the stretch of white sands outside of Danang that was dubbed 'China Beach' by American GIs on rest and recreation leave during the war.

US-Vietnam military relations were kickstarted in November last year with a landmark trip by Vietnamese Defence Minister Pham Van Tra to Washington for talks with his US counterpart Donald Rumsfeld.

Three years in the making, it was the first visit by the head of the communist nation's military since the US-backed Saigon regime capitulated on April 30, 1975 to the North Vietnamese onslaught.

Less than two weeks after Tra's Washington foray, the frigate USS Vandegrift made an historic and deeply symbolic port call in the former South Vietnamese capital, now called Ho Chi Minh City.

US-Vietnam diplomatic relations were only formalised in 1995 and five years later the two countries signed a trade pact, which triggered a dramatic increase in two-way trade.

Relations between the former foes remain strained, however, in particular over Washington's criticism of Hanoi's human rights record.

Last week Vietnam lashed out at at a decision by the US House of Representatives to restrict American aid to the communist nation because of human rights concerns, warning it could damage bilateral ties.

WAR.WIRE