TEHRAN — Iran is weighing a more confrontational strategy at possible renewed nuclear talks with world powers, threatening to boost levels of uranium enrichment unless the West makes clear concessions to ease sanctions.
Such a gambit — outlined by senior Iranian officials in interviews this week — could push Iran’s nuclear program far closer to the ‘‘red line’’ set by Israeli Prime Minister Benjamin Netanyahu for possible military options.
But it also suggests that economic pressures and diplomacy have pushed Iran to the point of considering an ultimatum-style endgame in efforts to seek relief from the US and European sanctions, which have targeted Iran’s vital oil exports and its ability to use international banking networks.
Mansour Haghighatpour, deputy head of Iran’s influential National Security Committee in Parliament, said 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 about 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 UN 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.