Russia’s top negotiator in Iran nuclear talks says intensive work is ahead and a last effort is needed to wrap up the negotiations to revive the 2015 agreement.

Mikhail Ulyanov twitted photos of the Monday evening meeting with JCPOA participants in Palais Coburg, saying, “Tremendous progress has been made since April 2021, when the talks started. But there is a rule: nothing is agreed until everything is agreed.”

He also tweeted about his meeting with chief Iranian negotiator Ali Bagheri-Kani saying that “intensive work is ahead of us to wrap up the negotiations on restoration of the JCPOA”.

Bagheri Kani returned to Vienna on late Sunday to continue the eighth round of talks with representatives of the five remaining parties of the JCPOA to resolve the remaining issues.

The Iranian diplomat, who had gone to Tehran last week to hold consultations and receive necessary directives, flew back from the capital as some Basij hardliners gathered at the airport to protest against the agreement.

They held placards with sentences echoing remarks by Supreme Leader Ali Khamenei and chanted “Death to the America.”

Iran's foreign ministry said on Monday that "97-98 percent" of a draft agreement is ready but three key issues remain that the West has not agreed with.