Lausanne, SWITZERLAND -- Under pressure to appease the skeptical Republican-led Congress, Secretary of State John Kerry is racing to reach agreement with his Iranian counterparts in the coming days.
The framework being negotiated would limit Iran's nuclear development for up to 20 years, with the most stringent technical limits hitting during the first 10 years. Additional monitoring would continue into at least the second decade.
Iran would also agree to cut the number of centrifuges it has running - that could be used to build a bomb -- from 10,000 to 6,000. That's essentially a 40% reduction, but diplomats emphasized that the exact figures could fluctuate, especially as the more difficult enrichment restrictions and political issues are still under discussion.
In return for those concessions, the emerging proposal would also offer quick relief from European Union sanctions and some US sanctions. However, it would not immediately lift the U.N. Security Council blockades. That is a frustration for Iran, which wants the U.N.-related sanctions removed as quickly as possible. A European diplomat told CBS News that was too much to ask given that negotiators wanted to be able to snap those sanctions back into place if Iran were to violate the deal.
Another incentive for Iran is the willingness of countries like France to offer guidance on how to improve its nuclear development if it is solely used for energy purposes.
Among the stickiest issues: Iran's refusal to agree to restrictions on its military program and its reluctance to allow inspectors to search military bases where some nuclear testing has been suspected. Iran's research and development around its nuclear program is also a concern - as are the clandestine installations at the Fordow nuclear facility. Iran is also arguing against proposals that would restructure its enrichment program to alleviate the fears of the P5+1 nations.
A U.S. official said that proposals were under discussion and that there were no written draft agreements being circulated among the negotiators.
Secretary of State John Kerry spoke briefly to reporters in between meetings and said that progress had been made. Yet a European diplomat who spoke with CBS News was far more pessimistic, calling the progress not sufficient enough to warrant an accord.