Prime Minister Hun Sen responded to the United States Embassy’s accusations that the Cambodian government had politicised the discovery and removal of ordnance in Svay Rieng province’s Koki commune, saying the Americans were trying to minimise their war legacy.

“In the past you dropped chemical weapons in Cambodia, but today you say it is tear gas instead,” he said during a Sunday speech to garment workers, referring to the tear gas bombs found in Koki commune. “Tear gas does not have an effect for over 40 years.”

The premier seemed to be referring to birth defects caused by the defoliant Agent Orange used by the US military in Cambodia, though the bombs discovered in the commune over the last year appear to contain substances that do not cause birth defects. The comments also seem to contradict statements by Heng Ratana, director of the Cambodian Mine Action Centre, saying the chemical substance found was chlorobenzalononitrile-2, a type of tear gas.

“Chemical bombs were dropped causing leaves to fall . . . Babies born with big heads, big eyes and irregular bodies,” Hun Sen said in the speech in an apparent reference to the effects of Agent Orange.

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The premier then invited officials from the US Embassy and the Peace Corps to visit the area.

“If possible, the US Embassy should bring some soil there to plant at the embassy,” he said.

The embassy declined to comment.