BOSTON (Reuters) - John Kerry's commanding officer in Vietnam has backed away from attacks on the Democratic presidential candidate, saying he made a mistake in accusing the U.S. senator of having lied about his wartime record.

George Elliott, who was one of Kerry's superiors in Vietnam when he was awarded medals for heroic actions, had signed an affidavit suggesting Kerry did not deserve the Silver Star.

In the document, Elliott said, "I was never informed that he had simply shot a wounded, fleeing Viet Cong in the back."

But in Friday's Boston Globe, Elliott said: "It was a terrible mistake probably for me to sign the affidavit with those words. I'm the one in trouble here."

Elliott told the newspaper he thinks Kerry did deserve the medal.

George Bush has added another verbal gaffe to his long list of blunders.

The latest addition to the catalogue of Bushisms came as he addressed Pentagon chiefs during the signing ceremony of a defence spending bill.The US President said: "Our enemies are innovative and resourceful, and so are we.

"They never stop thinking about new ways to harm our country and our people, and neither do we."