John Kerry speaks after signing of Iran deal
John Kerry speaks after signing of Iran dealCredit: Reuters

Speaking at a press conference following the signing of a nuclear deal with Iran earlier Tuesday, US Secretary of State John Kerry admitted that despite reaching a deal plenty of challenges still lie ahead.

"The fact of the signing of this agreement does not eliminate all of the challenges," Kerry emphasized. "It's the implementation that will matter."

"I'm not going to stand here and tell you that everything is going to work without a bump, without hitch in the road, without a misunderstanding or some effort that needs clarification," he told reporters.

"What I do know is that the negotiators absolutely affirmed to us on several occasions - and most imortantly in the last 24 hours - that they are operating with a full mandate from the president, Rouhani, and from the Supreme Leader."

That said, Kerry stated that he was confident the deal would be successfully implemented, given that the "consequences" for Iran of not doing so were clear.

But he admitted that he "can't vouch for" the fact that Iran will comply, and not simply reap the benefits of the deal while continuing to deceive inspectors as it has done in the past.

Kerry also sought to assuage fears of an immediate end to the arms embargo imposed on Iran, telling reporters the embargo would remain in place for five years to ensure Iran implements the deal during that time.

Israel and many Sunni Arab states fear the lifting of such sanctions will fuel and escalate conflicts throughout the region, where Iran is arming, financing and training a variety of terrorist proxies and other militias to expand its control over the Middle East.