Former American ambassador Harry Barnes, whom Bharatiya Janata Party leader Jaswant Singh has named as the recipient of a letter about a mole in the office of late prime minister P V Narasimha Rao, has said that he has no knowledge of the man who purportedly wrote the missive.

Singh had on Tuesday said in Parliament that Barnes had received a letter was written by US Senator Thomas Graham.

Barnes, who was the US envoy to India during 1981-85, denied knowledge of 'any Senator' going by the name Thomas Graham and said that the best way out would be to ask Singh himself to sort out the controversy over a spy who allegedly leaked nuclear secrets from the Prime Minister's Office to the US in 1995.

"I find the reporting very confusing," Barnes told PTI on phone from his home in Peachem, Vermont, adding: "I was not in India in 1995 (when the letter was purportedly written). I was the ambassador between 1981 and 1985."

Referring to reports linking him to a Senator Graham in connection with the letter, which has been referred to by Singh in his book A Call To Honour, the soft-spoken former envoy said, "I knew of no Senator Graham."

Barnes, however, said he knew two men with the same name. "A Thomas Graham was a representative of the Rockefeller Foundation and the second Thomas Graham was the head of the Arms Control and Disarmament Agency in the 1990s," he said.

"The dates are very confusing," Barnes said, while making the point that he had seen part of a published account of the letter that did not show his name.

More embarrassment came for the BJP and Jaswant Singh on Wednesday when the United States distanced itself from the purported letter on a PMO mole saying it was a 'fraudulent, poor imitation' of official US correspondence.

"The letter does not contain a shred of truth. The US was not asked to examine it (the letter) before its publication in newspapers. Had we been asked, we would have pointed out that it is fraudulent, a poor imitation of official US government correspondence," a senior Administration official told PTI.