The U.N. nuclear agency says Iran has significantly reduced its stockpile of highly enriched uranium under the requirements of an interim nuclear deal.
In a new report, the International Atomic Energy Agency says Iran has neutralized about 80 percent of its supply of higher-grade enriched uranium gas.
Enriching uranium to very high levels is a major step toward creating a nuclear weapon.
Iran denies Western charges that it aims to produce an atomic weapon. But under an interim deal with world powers reached last year, Iran agreed to some nuclear concessions in exchange for a partial lifting of the sanctions it faces for its atomic work.
Diluting and converting its highly enriched uranium stockpile were among the Iranian commitments under the agreement.
Officials hope to have a final agreement in place by July 20.
Iran insists its nuclear program is peaceful and is aimed at producing electricity and for medical treatment.