Vietnam is beginning a joint operation with the United States to remove traces of the toxic Agent Orange.

American forces sprayed up to 12 million gallons of the chemical throughout the 1960s to destroy vegetation cover for Communist forces in the Vietnam War.

Dioxin, a chemical used in Agent Orange, has been linked with cancer and birth defects.

Three Agent Orange hot spots have been identified in Vietnam, including the area around Da Nang Airport where the Americans once had a military base.

This area will be the initial focus of a joint clean-up operation.

First the Vietnamese will check for any unexploded ordnance then the Americans will join them to remove potentially harmful, dioxins from the soil and sediment.

US-Vietnam ties have blossomed since diplomatic relations were established 16 years ago and steps to resolve legacy issues from the war have formed a cornerstone of progress.

The top US diplomat in the country, Virgina Palmer, said the joint operation was of the most significant developments between the two countries.

"I think it's fair to say that dioxin contamination and Agent Orange was one of the single most neuralgic issues in the US-Vietnam relationship," she said.

The US Congress appropriated an initial $US3 million in 2007 for the effort and the figure has since leapt to $US32 million.

- BBC/Reuters