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.

ROME (AP) — Iran and the United States prepared for a fifth round of negotiations over Tehran’s rapidly advancing nuclear program Friday in Rome, with enrichment emerging as the key issue.

Iranian and U.S. negotiators will resume talks on Friday in Rome to resolve a decades-long dispute over Iran's nuclear ambitions, despite Tehran's supreme leader warning that clinching a new deal might be insurmountable amid clashing red lines.