"This is a highly exaggerated account. Somebody has let his imagination run wild," a senior government official told AFP, commenting on the statement in Vienna by an Iranian opposition group, National Council for Resistance in Iran.

The group's senior official, Farid Soleimani, claimed at a news conference that Khan "delivered a quantity of HEU to Iran in 2001."

The Pakistani official, who spoke on condition of anonymity, said Islamabad had shared the findings of its investigation into the international black market of nuclear proliferation with the international community.

"The government of Pakistan had shared findings of some illicit transfers by international blackmarketeers transparently with the people of Pakistan," the official said.

"It has also been cooperating with the IAEA."

Foreign ministry spokesman Masood Khan also dismissed the group's statement as "speculative claims made by individuals."

"Such a communication has to come formally either from the Iranian government or the IAEA before we can comment on it or look into it," Khan told

He said investigations in Pakistan were continuing, but that Islamabad had received no such information either from the Iranian government or the International Atomic Energy Agency.

Pakistan has refused to let the UN atomic agency directly interview Khan, considered the father of Pakistan's bomb, after his public confession in February to selling nuclear secrets to Iran, Libya and North Korea.

President Pervez Musharraf gave Khan a conditional pardon and said no government or military body was involved in the proliferation scandal.