Iran is negotiating with a group of six states over the future of its nuclear program. In November 2013, Iran and the P5+1 (China, France, Germany, Russia, the United Kingdom, and the United States) agreed to a Joint Plan of Action that seeks to reach a “comprehensive solution” by July 20, 2014.

The goal is an agreement on a set of measures that can provide reasonable assurance that Iran’s nuclear program will be used only for peaceful purposes and enable the lifting of international sanctions imposed on Iran over the past decade because of proliferation concerns.

A key challenge is to reach agreement on limiting Iran’s uranium-enrichment program, which is based on gas centrifuges, in a way that would enable Iran to meet what it sees as its future needs for low-enriched uranium (LEU) fuel for nuclear research and power reactors while forestalling the possibility that this program could be adapted to quickly produce highly enriched uranium at levels and in amounts suitable for use in nuclear weapons.

This article proposes a compromise based on a two-stage approach that involves Iran maintaining a capacity for enriching a small amount of uranium annually for research reactor fuel in the short term and developing a potential enrichment capacity in the longer term that would be appropriate to fuel power reactors. Iranian supply needs for its power reactors will develop in 2021 if Tehran decides to fuel the existing Bushehr power reactor domestically, in whole or in part, rather than renewing its fuel supply contract with Russia or buying fuel from another foreign supplier.

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See full text at the Arms Control Association: Agreeing on Limits for Iran’s Centrifuge Program: A Two-Stage Strategy