Disgraced Pakistan nuclear scientist A Q Khan smuggled several nuclear centrifuges to Dubai, some of which might have been transferred to Iran and North Korea, a senior Pakistani military official has said.

He also claimed that Pakistan was willing to subject Khan to lie detector test but could not do so as the United States did not provide the lie detectors. "If you ask for an educated and intelligent guess, I will say, yes, they (P-2 centrifuges) might have been sent to Iran too but we have no evidence to prove it," an official, who did not want to be identified, was quoted by Dawn newspaper as saying in an highly unusual briefing in Washington.

The briefing attended by American and Pakistani officials was held amid the North Korean nuclear crisis and was aimed apparently at assuring the international community that Islamabad [Images] was not involved in any proliferation efforts and that the network allegedly run by Khan has been completely uprooted.

Iran denies receiving P2 centrifuges, but international inspectors have found evidence of Pakistani centrifuges at Iranian nuclear sites.

A Pakistan defence delegation led by Gen Kidwai, who is the head of the country's strategic division in-charge of the nuclear programme, is currently visiting the US addressing various think tanks there.

The official said in 1995, long after Pakistan had discarded using the old P1 machines, Khan ordered 200 P1 centrifuges out of Kahuta to Dubai, which were then sent to Iran.

Asked if he knew how many P2s were smuggled out, he said 'three or four P2s were sent to Dubai.'

The official also said that Pakistan had no objection to subjecting Khan to a polygraph test to determine if he was telling the truth to his interrogators, but the Americans refused to supply lie-detectors to Islamabad.

He said the government could never allow a foreign agency to interrogate Khan because he was still considered a national hero.

"There is not a single Pakistani who does not consider him a national hero. It will be a highly controversial move and the political repercussions will be huge."

The official said despite suffering from initial stages of prostate cancer, Khan was fit for interrogation.