Six major powers and Iran have decided to extend their talks until Thursday after failing to narrow their differences on a framework agreement to limit Tehran's nuclear program.
The six countries — Britain, China, France, Russia, the United States, and Germany — and Iran had aimed to strike the deal by Tuesday, with the aim of reaching a final accord by the end of June.
According to a negotiation source, Iran has agreed to scale back its uranium enrichment program to some extent but insisted that it will continue its research and development on ultra-centrifuges.
Noting that negotiations appear to have hit a snag, Iranian Foreign Minister Mohammad Javad Zari told reporters that conflicting opinions among the six countries have complicated the issue.
Marie Harf, a U.S. State Department spokeswoman, said that the six parties and Iran have yet to agree on a deal and Secretary of State John Kerry will stay in Lausanne, Switzerland, to engage in the negotiations at least until Thursday morning.