Kerry heads to Vienna to talk Iran deal

US Secretary of State John Kerry heads to Vienna on Saturday for talks with his European Union and Iranian counterparts on the Iran nuclear deal, officials said.

The trip comes amid speculation that the Vienna-based IAEA nuclear watchdog is about to announce Iran has fulfilled its side of the deal to put an atomic bomb beyond its reach.

State Department spokesman Mark Toner said Kerry will meet with Iranian Foreign Minister Javad Zarif and EU foreign policy chief Federica ‎Mogherini to discuss the so-called Joint Comprehensive Plan of Action on Iran's nuclear program.

"As we've said, all parties have continued making steady progress toward 'Implementation Day' of the JCPOA, which will ensure the exclusively peaceful nature of Iran's nuclear program," Toner said.

International and US officials have refused to confirm that implementation of the agreement will begin Saturday, but agree that it will start in the coming days and Iran expects it before Sunday.