Iranian President Hassan Rouhani speaks during a cabinet meeting in Teheran on April 7, 2021. (PHOTO / AFP)

Iran's President Hassan Rouhani said negotiations on how to the revive the 2015 nuclear deal were 60 percent to 70 percent complete and could be resolved quickly if the US acts with “honesty,” according to a statement on his official website.

World powers including China, Russia and the European Union on Tuesday concluded their latest round of talks in Vienna aimed at returning the US to the accord that then-President Donald Trump abandoned in 2018, and rolling back Iran’s atomic activity to within the agreement’s limits.

Iran’s lead negotiator, Abbas Araghchi, said that while talks were “on the right track,” challenges remained. Delegates will next week focus on sequencing, or how the US and Iran will choreograph the steps they need to take to fully restore the deal, he said

Iranian negotiators have "completely followed the framework designated by Iran's Supreme Leader Ayatollah Ali Khamenei," Rouhani told a group of political activists in Tehran, as quoted by official IRNA news agency.

Khamenei has insisted that US sanctions must be lifted before Iran returns to its compliance with the Iran nuclear deal, known as the Joint Comprehensive Plan of Action (JCPOA), and warned against the country's participation in drawn-out talks.

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Iran’s lead negotiator, Abbas Araghchi, struck a more cautious note earlier in the day, saying that while talks were “on the right track,” challenges remained. Delegates will next week focus on sequencing, or how the US and Iran will choreograph the steps they need to take to fully restore the deal, he said.

Vienna talks have so far progressed to a large extent, the Iranian president said, adding that if Washington moves with honesty, the negotiations will reach a conclusion "in a short time." 

The crisis over Iran’s nuclear program has convulsed the Persian Gulf ever since Trump withdrew and reimposed American sanctions on the Islamic Republic, fueling proxy conflicts and leading to a spate of attacks on shipping. It escalated last week as Tehran began enriching uranium closer to weapons grade after an unclaimed attack on its top nuclear facility.

The US hasn’t commented on the Iranian statements. The EU’s lead mediator, Enrique Mora, said in a tweet that while progress had been made there was “much more hard work needed.”

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Rouhani said that while Iran was in “no hurry” to revive the deal, his government wanted to make the most of the opportunity.