"Those who are making accusations are illiterate. They don't have any knowledge about it. So it won't be right to further comment on it," Singh told media.
Over the involvement of Reliance group in the Rafale deal, Singh stated that the authorities from the group have already spoken on the issue and that there is no point dragging the matter, taking names, news agency ANI reported.
Singh's remarks came after Congress president Rahul Gandhi on Wednesday stated that a probe into the procurement of Rafale fighter jets from France would throw up names of Prime Minister Narendra Modi and Anil Ambani; Gandhi was addressing a rally in Chhattisgarh.
Gandhi also claimed the NDA government bought the planes at Rs 1,600 crore a piece as against the Rs 526 crore for each aircraft fixed by the Congress-led UPA government.
Rahul Gandhi's comments came on a day the Supreme Court said a discussion on the pricing of the Rafale jets can only take place if the facts of the deal are allowed to come into the public domain.
The apex court, which began its hearing on pleas seeking a court-monitored probe into the procurement of 36 Rafale fighter jets from France, also said it would like to hear from an Air Force officer and not an official of the Defence Ministry.
"The CBI director (Alok Verma) initiated a probe in the Rafale deal. The prime minister removed him at 12 in the night. I am telling you, the day a probe will begin in Rafale deal, two names will surface: Anil Ambani and Narendra Modi," Gandhi told the gathering.
On former French president Francois Hollande's comments in French media that the Indian government had proposed Reliance Defence as a partner for Dassault Aviation in the deal and that France did not have a choice, Gandhi said Modi named Ambani's company as Dassault's partner in the Rs 58,000 crore Rafale deal, news agency PTI reported.
The Modi government chose Ambani's "inexperienced" company over the Hindustan Aeronautics Limited (HAL) which has a long experience in the aerospace and defence sector, PTI quoted the Congress president.
(With inputs from agencies)
During a rally in Chhattisgarh, Congress president Rahul Gandhi stated that a probe into the procurement of Rafale fighter jets from France would throw up the names of PM Modi and Anil Ambani.