Kerry will head to Geneva to help clinch Iran nuclear deal -U.S

AMMAN (Reuters) - U.S. Secretary of State John Kerry will travel to Geneva on Friday in an effort to help secure a nuclear deal between Iran and six world powers, a senior U.S. State Department official said. "Secretary Kerry will travel to Geneva, Switzerland on Friday at the invitation of EU High Representative (Catherine) Ashton in an effort to help narrow differences in negotiations," the official said. Diplomats in Geneva said work on a possible deal aimed at ending a decade-long nuclear standoff between Iran and the West was continuing. Iranian officials said on Thursday that they were cautiously optimistic about prospects for an agreement but noted that nothing had been finalized. (Reporting by Lesley Wroughton; writing by Louis Charbonneau)