Former external affairs Minister Jaswant Singh is understood to have forwarded to Prime Minister Manmohan Singh [Images] the name of a 'mole' in Prime Minister's Office (during P V Narasimha Rao's tenure) who he alleged had leaked India's nuclear test plans to the US, a day after Singh dared him to name the person.

Party sources said Jaswant Singh has forwarded the letter purportedly written by a US diplomat to a Senator, which has a reference to the 'mole' in the PMO during Rao's tenure.

"He (Jaswant Singh) has told us that he will be sending the letter to the prime minister without deleting any names. By now, he must have forwarded the letter," Bharatiya Janata Party Deputy Leader in the Rajya Sabha Sushma Swaraj told PTI.

The prime minister had Sunday rubbished Singh's claims and said, "If he (Jaswant) has the decency and courage, he should name the person whom he is accusing of being a mole. We are not afraid of any debate on any issue".

The BJP leader, on his part, expressed disappointment with the phraseology the prime minister chose to use "in challenging decency."

"I am actually not given to indecent exposure and he does not have to challenge me. I will seek a time with him. I will go and give him the document that I have, but I will not make public the names, because there is a national purpose behind it," he told the television channel CNN-IBN.

Meanwhile, Parliamentary Affairs Minister P R Dasmunsi said, "If Singh has done so (forwarded the document to the prime minister), we will make it public."