Iran nuclear talks advancing, no deal likely next week -U.S. official

(New throughout, adds quotes, details, background) By Arshad Mohammed WASHINGTON, Feb 27 (Reuters) - Talks on curbing Iran's nuclear program have made substantial progress, a senior U.S. official said on Friday as the White House braced for an onslaught of criticism next week from Israeli Prime Minister Benjamin Netanyahu. The official told reporters many hurdles remained to reaching an agreement to restrain the Iranian nuclear program in exchange for easing economic sanctions and said he did no