The fifth round of Iran-US nuclear talks ended without progress as uranium enrichment remains a key issue amid rising tensions and new sanctions.- Watch Video on English Oneindia

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 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.

Iran and the United States are preparing for a fifth round of negotiations over Tehran’s rapidly advancing nuclear program, with enrichment emerging as the key issue

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.