Secretary of State John Kerry says he is returning to Washington, D.C., to consult with President Obama following talks with Iran over its nuclear program. Speaking on Tuesday, Kerry cited "tangible progress" on key issues, but said "very real gaps" remain ahead of a Sunday deadline. Iranian Foreign Minister Mohammad Javad Zarif says Iran could freeze its nuclear capacity in exchange for sanctions relief, but Kerry would not say if the United States would agree. The main dispute is over Iran's uranium enrichment program, which Tehran claims it will need to expand to fuel its nuclear power reactor. The United States counters that this would allow Iran to enrich enough uranium at a high level to make a nuclear weapon, and wants Tehran to cut back sharply on its enrichment capability for as long as 20 years.

Iran John Kerry Nuclear Tehran