"I would propose that Iran's adhesion to the NPT be suspended for as long as the problems created for Iran in the (International Atomic Energy) Agency (IAEA) are not resolved," Reza Amrollahi, a former head of the national atomic energy organisation, told the hardline Jomhuri Islami newspaper.
Iran signed the NPT, the cornerstone of global efforts to stop the spread of nuclear weapons, back in 1970 when it was still ruled by the shah.
But the country is now locked in a bitter dispute with the IAEA over US-led accusations that it is using a bid to generate nuclear energy as a cover for weapons development.
Amrollahi said Iran should also review ratification of the additional protocol of the NPT, a tighter inspections regime which the regime signed up to in December last year.
"We should also suspend the process of adopting the additional protocol while these problems persist," he told the paper.
The protocol has yet to be ratified by parliament, which is now in the hands of religious conservatives. Its signature and the suspension of uranium enrichment were key parts of a deal brokered by Britain, France and Germany last October to address US concerns.
Iran insists it has now fully cooperated with the IAEA, and accuses the agency of bowing to pressure from the United States.
The IAEA's board is currently discussing a British-French-German draft resolution that calls for investigation of Iran's nuclear programme to be stepped up, and chastises the clerical regime for failing to allay suspicions.
On Wednesday, President Mohammad Khatami said Iran would feel "no moral obligation" to adhere to key commitments to the IAEA if Iran were slapped with yet more criticism, but he dismissed any immediate talk of quitting the NPT.