BBC and khabar network

MUSCAT, Oman — The urgent quest for a breakthrough in talks to rein in Iran’s nuclear capacity led negotiators to meet into the night Sunday with a deadline looming over their heads.
Secretary of State John F. ­Kerry, Iranian Foreign Minister Mohammad Javad Zarif and Catherine Ashton, the European Union’s foreign policy chief, met for three hours in the early afternoon, and more than two hours more after nightfall. A U.S. official said talks would resume here at the meeting site, a resort along a scenic beach between the Hajar Mountains and the Indian Ocean, on Monday morning.
The mere fact they are still at it suggests progress is still possible, as more than a decade of negotiations boil down to the final two weeks before a Nov. 24 deadline. If the date passes without a deal or an extension, an interim pact dies, dealing a potentially fatal blow to the international effort to keep the Islamic republic from building a bomb.
Important differences remain unresolved, including the level of uranium-enrichment capacity Iran will be permitted to retain, and the pace for phasing out international sanctions.
For the United States and its five negotiating partners, the goal is to make sure that all pathways to an Iranian bomb would be visible and time-consuming. Iran seeks relief from the punishing sanctions hobbling its economy when falling oil prices are strangling revenue.