Nuclear deal elusive as Iran, six powers resume talks in New York

United Nations: A diplomatic breakthrough is unlikely on a nuclear deal to end sanctions against Iran when talks resume in New York this week between Tehran and six world powers deadlocked after a year of negotiations.

The talks between Iran and the United States, Britain, France, Germany, Russia and China are re-starting after a two-month hiatus and amid Washington and Tehran ruling out cooperation on fighting Islamic State militants who have taken over swaths of Iraq and Syria.

Iranian Foreign Minister Mohammad Javad Zarif and European Union foreign policy chief Catherine Ashton will discuss the negotiations on a long-term nuclear deal over lunch on Thursday, diplomats said. The EU has been a kind of interlocutor for the six powers.

Diplomats from the six countries will begin meeting among themselves on Thursday before they all sit down with the Iranian delegation on Friday. The negotiations are expected to run until at least Sept. 26 on the sidelines of next week`s annual gathering of world leaders at the United Nations General Assembly.

U.S. Under Secretary of State for Political Affairs Wendy Sherman, who heads the U.S. delegation, said in a speech at Georgetown University on Tuesday that more movement from Iran will be needed to secure a long-term agreement.

"We can say on the positive side that our talks have been serious and that we have identified potential answers to some key questions," Sherman said. She also said "we remain far apart on other core issues, including the size and scope of Iran`s uranium enrichment capacity."

Iran denies Western allegations that it is refining uranium to develop the capability to assemble nuclear weapons, saying it is doing it to help generate electricity.

The United States and its allies have in recent years imposed ever tighter financial and others sanctions on Iran, a major oil producer, to make it scale back its nuclear program.