Iran’s recent overtures aim to ease the stranglehold of sanctions and facilitate Tehran’s re-engagement with the international community. Is Tehran prepared for serious concessions? Are there options for a reasonable settlement that can meet Iranian and U.S. redlines?

Sanctions have isolated Iran from energy markets and the global financial system. Oil exports, which generate nearly half of Iran’s revenues, have fallen by nearly 60 percent since 2011. Iranians struggle to conduct routine financial transactions such as securing letters of credit.

In public statements, Iranian leaders claim that further progress on the nuclear program would backfire. Troubles in Syria notwithstanding, the regime maintains that it is in a strong regional position. Iran has achieved key threshold capabilities in its nuclear program and enjoys conventional and unconventional military superiority over many other regional powers. Iran’s leaders acknowledge that proceeding too far along the enrichment path could provoke rivals such as Saudi Arabia and Turkey to ramp up their own nuclear programs. Nor does Tehran discount the possibility of further sanctions, not to mention a U.S. or Israeli military strike. These statements are encouraging, assuming that they reflect the regime’s genuine strategic calculus.

Iran’s leaders are using more moderate language at home as well. Supreme Leader Ayatollah Khamenei has endorsed a policy of nermash qaramona—“flexibility of the hero.” Iranian leaders are invoking the Imam Hassan, who accommodated the rule of the Sunni leader Muawiyah for the sake of peace in the Muslim world. By praising Hassan, the regime may be bracing the religious establishment for compromise.

If Iran’s conciliatory statements reflect a true policy change, domestic discontent may be the most important factor influencing Khamenei. A broad cross-section of the Iranian public, particularly its younger generation, supports Iran’s reintegration with the world. While talks with the West risk a backlash from hardline elements, further isolation could produce even greater pressure for change.

Rouhani enjoys both a reputation as a moderate as well as a close relationship with Khamenei. The new president, having served as the supreme leader’s representative on the National Security Council, may avoid the fate of his more pragmatic predecessors, whose diplomatic initiatives on the nuclear issue were undermined by Khamenei and his hardline allies.

Favorable rhetoric notwithstanding, the deal that Tehran is pursuing would not satisfy U.S. concerns. Without becoming an official nuclear state, Iran seeks the capability to produce a large number of nuclear weapons within a short time period. In his outreach to U.S. policy experts in New York, Rouhani affirmed that the fuel needs of its civilian nuclear-power plants should determine the size of Iran’s enrichment capability. Nor has the regime agreed to ship enriched nuclear fuel to Russia. Iran claims a right to industrial production of enriched uranium as well as a stockpile of partially enriched material—in effect, an industrial-level enrichment capability that could cloak the development of enough enriched material for a nuclear arsenal.

Allowing Tehran to maintain a stockpile of low and medium-enriched uranium would limit the warning time that the international community would have in responding to an Iranian breakout. According to IAEA estimates, Iran, as of mid-August, was maintaining a stockpile of 6,774 kg of low-enriched uranium gas, 186 kg of medium-enriched uranium gas, and the equivalent of 187 kg of medium-enriched uranium gas held in oxide form.

Still, the prospect for a more reasonable agreement, however small, warrants negotiations on two tracks.

The immediate challenge is to ensure that Iran does not enhance its nuclear capabilities during the negotiating period. Washington should stick with the current sanctions policy unless inspectors can verify that Tehran has frozen the nuclear program.

A verified freeze could open the door to a deal that addresses three core issues: Iran’s enrichment of uranium, the heavy water plant at Arak, and Iran’s acceptance of a verification regime.

Given Iran’s violations of the Nuclear Nonproliferation Treaty and various UN Security Council resolutions, any comprehensive deal should ideally force Tehran to cease all enrichment. Iran’s ten-year contract with Russia will supply enough fuel for the country’s only nuclear-power plant at Bushehr. Even if Tehran follows through on plans to build more nuclear-power plants, it will not be able to do so for at least another decade.

Insisting on zero enrichment, however, may needlessly scuttle talks. Basic U.S. interests would be secured by a compromise agreement in which Iran ships its stockpile of enriched uranium out of the country and mothballs its current enrichment facilities. The international community could recognize Iran’s right to enrich. In exchange, Iran would forgo enrichment until the international community determines that enrichment is the only option available to fuel Iran’s civilian power plants economically. Based on current projections, this would not occur for over a decade. Even then, imports would likely remain a cheaper source of fuel than domestic enrichment. The IAEA would assess the state of Iran’s civilian power plants and the reopening of enrichment facilities would be subject to the international community’s approval.

A compromise along these lines would put the United States in a better position, but would entail significant risks as well. If Iran were to renege, open its enrichment facilities, and break out of the nonproliferation regime, Tehran would have a substantial enrichment infrastructure. The international community would need to act decisively in response to Iran’s violation of the accord.

A third option may prove amenable to Iran while entailing more manageable risks for the United States. Iran could preserve a limited enrichment capability, but one scaled to give at least two year’s warning time in case Iran decides to enrich in pursuit of a bomb. Two years would provide Washington with enough time to reimpose sanctions or take military action.

The United States could present Iran with a choice. Iran can ship its entire stockpile of enriched uranium gas and oxide to a third country and retain about 2,500 IR-1 centrifuges—less advanced, first generation systems. Such an agreement would require Iran to destroy large numbers of the 15,500 IR-1 and over 1,000 more capable IR-2m centrifuges that it has already installed. This would mean that Iran’s residual capability would need two years, starting with natural uranium, to enrich enough fuel for a bomb. Alternatively, Iran could keep some of its current stockpile in country but retain a smaller number of centrifuges, with the specific number set to leave two year’s warning time of any possible breakout.

Allowing Iran to retain one year’s supply of fabricated fuel rods for the Bushehr plant would satisfy its concerns about energy security. Converting reactor fuel into bomb-grade material is a complex process, readily detectable by inspectors, which would provide sufficient warning time in the event of an attempted breakout.

While the enrichment issue permits some flexibility, the international community must insist that Iran dismantle its heavy water plant at Arak. If the Arak plant becomes operational in 2014, as scheduled, Iran would be able to reprocess plutonium for the core of a nuclear weapon. Eliminating the Arak facility is necessary to deny Tehran an alternative route to weapons-grade material.

Finally, a comprehensive deal should require Tehran’s cooperation with a comprehensive inspections regime. Iran must sign the Nonproliferation Treaty Additional Protocol and the Modified Code 3.1 of the Subsidiary Arrangements General Part to Iran’s Safeguards Agreement, which would enable the IAEA to achieve a full accounting of the country’s nuclear programs, capabilities and facilities. The regime must acquiesce to inspections anytime anywhere, and grant inspectors full access to all military facilities and key personnel. Only under these conditions can on-demand inspections monitor hidden nuclear facilities. Intrusive inspections would punish Iran for contravening the NPT and the UN Security Council, thus deterring other would-be proliferators.

The international community can reciprocate by lifting the most onerous sanctions—those that restrict Iranian access to oil markets and the global financial system. Other sanctions would remain in place to address the regime’s transgressions on terrorism, regional meddling and human rights.

This deal would entail costs for both sides. Iran’s current capabilities would be rolled back. But the nonproliferation regime would weaken. The threat of an Iranian breakout would remain. And a sanctioned violator of the NPT would retain enrichment capability.

Still, such an agreement would preserve important interests for both sides and avoid a potential military conflict. It would allow Iran a civilian nuclear power program as well as a face-saving solution to its demand for enrichment capability. The international community would have sufficient warning time between Tehran’s decision to renege on the agreement and the regime’s ability to build a nuclear weapon, as Iran would have to expel inspectors, reconstitute its enrichment capability, and start enrichment from either natural uranium or a diminished stockpile of partially-enriched material.

Iran may simply be seeking to deceive, manipulate, and divide the international community. But a limited window still exists to test Tehran without lifting existing sanctions or escalating the conflict. Having engaged and offered reasonable options for a settlement, Washington would be in stronger position to sustain current policies and enact tougher measures if necessary.