Mansour Haghighatpour, deputy head of Iran's influential National Security Committee in parliament, told the Associated Press that the hard-line negotiating formula under consideration would put Western negotiators on notice that failure to ease sanctions could open the way for uranium enrichment above 20 percent - currently the highest level acknowledged by the Islamic Republic.
That would mark a dramatic move toward the threshold for warhead-grade material at around 90 percent and certainly bring a sharp escalation in calls for military action from Israel and others in the West. Iran denies it seeks nuclear weapons, but there have been suggestions it could ramp up uranium enrichment for future projects such as nuclear-powered submarines.
"The West now has a chance to strike a deal with Iran," Haghighatpour said in an interview. "Perhaps we may need to produce nuclear fuel for large commercial vessels that need 60 percent purity."
There are no immediate plans to resume nuclear talks between Iran and a six-nation group including both Tehran's foes and allies: the permanent U.N. Security Council members plus Germany. Full-scale negotiations have been on hold since the last round ended in stalemate in June.
At the time, the West stuck to its major demands: Iran must stop enriching uranium to 20 percent purity, shut down its underground Fordo enrichment site, and ship its 20 percent stockpile out of the country. In return, Iran was offered civilian plane spare parts and 20 percent-enriched nuclear fuel for its medical research reactor in Tehran.
But there was no move to ease sanctions - which have grown even tighter since the last negotiating session.
So far, Iran has publicly repeated its positions that it was willing to bargain over 20 percent enrichment as part of step-by-step moves to lift sanctions. Iran also wants an international pledge that it has the "right" to make its own nuclear fuel - at least at lower levels for its energy-producing reactor.
The tougher line outlined by officials has not been made public, and it's still unclear whether it will be adopted as a negotiating position. But the fact that it's under review suggests Iran is eager for a sweeping deal to lift sanctions and could try to jolt the West with a now-or-never choice: Roll back the sanctions or face a stepped-up Iranian nuclear program.
"The West feels sanctions are biting, and this is forcing Iran to return to the negotiating table. That's wrong. We never left the table. Sanctions have been harmful but will never make us give up our nuclear activities," said lawmaker Hossein Naqavi, spokesman for the parliament's Security Committee. "Pressures, sanctions and military threats won't make us retreat."