Unless Iran responds positively to President Obama’s offer of talks on its nuclear program by next month, it could face what Secretary of State Hillary Clinton calls "crippling sanctions.”

That was the message from Administration officials touring the Middle East in recent weeks.

And it’s backed by congressional moves to pass legislation aimed at choking off the gasoline imports on which Iran relies for almost a third of its consumption, by punishing third-country suppliers.

It sounds impressive and, for an undiversified economy like Iran’s, potentially calamitous. But a number of Iran analysts are skeptical that new sanctions will break the stalemate.

President Mahmoud Ahmadinejad’s government has promised to present a new package of proposals on the nuclear issue to Western negotiators in the coming weeks.

But that package is unlikely to reflect any shift in Tehran’s rejection of the U.S. demand that it forgo the right to enrich uranium as part of its nuclear-energy program.

"If the U.S. position remains unchanged,” says Farideh Farhi, an Iran expert at the University of Hawaii, "Iran may well come to the table, but only in order to demonstrate to its own people that its regime has been recognized, not to seriously engage with U.S. proposals or give ground.”

Iran’s postelection turmoil has left Ahmadinejad politically weakened, and his focus in the coming weeks will be on assembling a government and stabilizing a divided regime, rather than on seeking a compromise with the Western powers he blames for the election debacle.

"Iranians have never responded well to deadlines and red lines,” says Farhi, "and there’s no reason to believe they will do so now.”

In a TV interview two weeks ago, Secretary of State Hillary Clinton told Iran, "You have a right to pursue the peaceful use of civil nuclear power. You do not have a right to obtain a nuclear weapon.

You do not have the right to have the full enrichment and reprocessing cycle under your control.” But both the Iranian government and its opposition believe that Iran is due the same rights as any other signatory to the Nuclear Non-Proliferation Treaty, which includes the right to enrich uranium to the levels necessary for reactor fuel, under the supervision of the International Atomic Energy Agency (IAEA).

"There is no disagreement among political leaders in Iran on proclaiming Iran’s right to enrich uranium,” says Farhi.

Iran’s previous government had shown flexibility on the pace of an enrichment program, but not on the principle.

Explains Farhi: "It is simply not feasible for any political leader in Iran to accept an arrangement that denies Iran the rights enjoyed by others, that treats Iran as a special case.” Iran’s current enrichment efforts are monitored by IAEA inspectors and certified as within permissible limits.

The U.S. Director of National Intelligence, Admiral Dennis Blair, recently wrote to Congress that "it is unlikely that Iran will have the technical capability to produce [weapons-grade uranium] before 2013”.

Blair added that U.S. intelligence believes Iran has not yet decided whether to produce weapons-grade materiel, and would be unlikely to do so while its nuclear effort remains under international scrutiny.

But with hawks painting Iran’s nuclear program as a grave and gathering danger and the Israelis threatening to take preemptive military action, the Obama Administration is under pressure to produce results from its efforts to engage Iran.

Effective sanctions, say Administration officials, require participation by Iran’s key trading partners.

That’s a problem, since neither Russia nor China is convinced that there’s an imminent danger of Iran producing nuclear weapons. Coalition of the willing–style sanctions of the sort envisaged by the congressional legislation may have limited impact because they’re unlikely to be implemented by neighbors such as Turkey and Iraq.

And the use of naval power to enforce a blockade could easily provoke a war that the U.S. military is eager to avoid.

But even if "crippling sanctions” were somehow imposed, Tehran still might not back down.

"If it were possible to choke off the gasoline supply into Iran, the likelihood is that Iran’s existing refinery capacity would be used first and foremost to ensure that the needs of the security forces and the regime are taken care of,” says Dr. Gary Sick, a Columbia University professor and former National Security Council Iran specialist.

"Those who are going to suffer most will be the ordinary Iranians with whom we sympathize. You can argue that this might spur them to revolt, but more likely is that if their fuel rations are suddenly cut in half, ordinary Iranians will be very upset with the West.”

"The economic well-being of the Iranian people has never been a first-tier priority for the Iranian regime,” says Carnegie Endowment Iran analyst Karim Sadjadpour.

"The last three decades have shown us that this regime is willing to endure tremendous hardship rather than compromise for reasons of economic or political expediency.”

Farhi points out that Iran’s regime began making preparations for U.S. petroleum sanctions as early as 2007, diversifying its sources of supply, moving to upgrade its refineries and implementing a comprehensive rationing system, all of which can help the regime manage the impact of a fall in gasoline imports.

So what can the West possibly do? A number of Iran watchers recommend that in the postelection turmoil the Obama Administration should simply reset its clock.

"We should continue to allow the rifts between political élites, and the rift between the people and regime, to widen on their own,” suggests Sadjadpour. "As Napoleon once said, ‘If your enemy is destroying himself, don’t interfere.’

The truth is, we don’t know how sanctions on refined petroleum could play out, and our bottom line should be to do no harm to the prospects for political change in Iran.”

Easy enough for policy analysts to say, but not for a President. "A lot of people are going to be putting immense pressure on President Obama to set a deadline and take firm action,” says Sick.

The Administration may have no good options beyond continuing to explore diplomacy, he warns, but "it’s extraordinarily difficult to sell that to a chorus of people shouting ‘Do something!’”

Ends