The mother of an American killed in last month's Libya consulate attack has said his death has been used by the Romney campaign for political purposes, BBC News said.

The Republican presidential nominee has been citing his meeting some years ago with former U.S. Navy Seal Glen Doherty.

His campaign said the candidate would respect Barbara Doherty's wishes and stop mentioning her son.

The attack on the consulate in Benghazi on 11 September has become a political issue ahead of the election.

Doherty was killed in the attack in Benghazi along with Ambassador Christopher Stevens and two other officials.

"I don't trust Romney," Mrs Doherty told Boston news station WHDH.

"He shouldn't make my son's death part of his political agenda. It's wrong to use these brave young men, who wanted freedom for all, to degrade Obama," she said.

Campaigning on Tuesday in the state of Iowa, Mr Romney said that instead of running away from danger during the Benghazi consulate attack, Doherty had run towards it.

He reportedly used the anecdote as a metaphor for what Republicans must do to regain the White House in November's poll.