With just days before the November 24 deadline for reaching a diplomatic solution to the standoff over Iran’s nuclear program, Tehran’s politically-driven insistence on maintaining its current uranium enrichment capacity is standing in the way of a comprehensive agreement.

To overcome the remaining gaps and reach a deal, Iran and the United States must both be willing to exercise some flexibility.

For months, Iran has sought to maintain its current number of operating centrifuges—approximately 10,200. Iran also wants to be able to increase its uranium enrichment capacity over time to provide fuel for nuclear power reactors. Russia currently supplies Iran’s only nuclear power plant, and will continue to do so through 2021. And while Iran has plans to build additional nuclear power plants, these reactors are at least a decade away from operating.

The United States and its P5+1 negotiating partners want Iran to cut the current number of operating centrifuges for several years and to disable machines that are installed but not yet operating.

Given Iran’s record of hiding its nuclear program in the past, suspicion over its nuclear intentions is justified, particularly when its uranium-enrichment capacity exceeds its needs on the ground. Iran should be willing to accept a reduction in its enrichment capacity for a period of several years. This capacity could be allowed to expand in the future if Iran’s needs for enriched uranium increase.

Reducing Iran’s current enrichment capacity by half, combined with a significant reduction in the size of Iran’s enriched-uranium stocks or removal of those stocks to a third country, would increase the time it would take Iran to produce enough weapons-grade enriched uranium gas for one nuclear weapon to nine to 12 months or more. That is more than enough time to detect and disrupt any effort to develop nuclear weapons.

Fuel guarantees, including the shipment of several years worth of fuel to Iran for the Bushehr reactor at the outset of any deal could help assure Tehran that its fuel needs will be met during the duration of an agreement.

The United States and its P5+1 partners, meanwhile, have sought to prevent any Iranian research and development on more advanced types of centrifuges. Tehran maintains that its research and development programs on more efficient centrifuge machines are Iran’s right and should not be limited during an agreement. Washington and its partners are concerned that work on advanced centrifuges could allow Iran to move quickly toward nuclear weapons, if it chose to do so.

But it is unrealistic to expect Iran to maintain its first-generation centrifuges, which are inefficient and unreliable. Any research and development program in a final deal would take place under strict international monitoring. Restrictions could also be put in place that prevents Iran from manufacturing more advanced centrifuges in production scale quantities for a set duration.

Iran and the P5+1 have made progress on a number of important issues that appeared to be intractable just a year ago. They found a win-win compromise approach regarding Iran’s heavy-water reactor under construction at Arak that will still allow Tehran to complete the reactor, but with a modified design so that it produces far less weapons-suitable plutonium.

The two sides have found a way to resolve differences over the future of Iran’s smaller, underground uranium enrichment plant at Fordow. The two sides have agreed in principle that Iran will not have to close the site but would repurpose it for research and development so that it is not producing enriched uranium.

A similar solution is possible on the uranium enrichment question, but Iran and the US and its P5+1 partners have to exercise more flexibility in order to get there.

A comprehensive, verifiable nuclear deal that limits Iran’s program in exchange for phased sanctions relief is within reach. Neither side should jeopardize the chances for a deal by holding on to hardline positions on the remaining issues.