Iran and the United States concluded a fifth round of high-stakes nuclear talks in Rome on Friday amid growing skepticism in Tehran about the chances of a deal as Washington hardens its position.

Iran has multiple major sites associated with its rapidly advancing nuclear program, now the subject of several rounds of negotiations with the United States

Iran's top diplomat warned Thursday that his country would take “special measures in defense of our nuclear facilities” if Israel continues to threaten Tehran's atomic sites, raising the stakes further ahead of a new round of talks with the United States.

DUBAI (Reuters) -Israel will receive a "devastating and decisive response" if it attacks Iran, Tehran's Revolutionary Guards said on Thursday, days after CNN reported U.S. intelligence suggesting Israel was making preparations to strike Iranian nuclear facilities.

Iran's Supreme Leader Ayatollah Ali Khamenei slamm ed U.S. demands that Tehran end its uranium enrichment program, stating that he does not believe ongoing nuclear negotiations with the U.S. will yield results. Iran says its nuclear program is for civilian purposes and that its enrichment program is a source of national pride and not negotiable.

Iran is moving ahead according to its national interests without being told what to do by outsiders, Head of the Atomic Energy Organization of Iran (AEOI) Mohammad Eslami stressed.