TEHRAN - The European Union coordinator for nuclear talks between Iran and world powers said on Friday he will meet with Iran’s chief nuclear negotiator in Tehran on Saturday.

Enrique Mora said he will meet Iranian deputy foreign minister and chief nuclear negotiator Ali Bagheri Kani in Tehran to try to close “the remaining gaps” in the Vienna talks aimed at reviving the 2015 nuclear deal, officially called the Joint Comprehensive Plan of Action (JCPOA).

“We must conclude this negotiation. Much is at stake,” Mora wrote on Twitter.

According to ISNA, Mora is expected to hold talks with some other Iranian officials as well during his visit.

Mora is reportedly expected to visit Washington shortly after the Tehran visit.

However, ISNA said the talks in Tehran will take place on Sunday and in Washington on Monday.

The talks appeared close to an agreement earlier this month but were then paused following last-minute demands by Russia.

The visit comes more than two weeks after EU foreign policy chief Josep Borrell called for a pause in the talks in Vienna due to “external factors”.

The pause came days after Moscow said it wanted written guarantees from Washington that Russia’s economic and military cooperation with Iran would not be harmed by Western sanctions imposed on Russia over its invasion of Ukraine.

Talks aimed at reviving the JCPOA have been taking place in Vienna for almost a year. The U.S. is participating indirectly in the talks due to Tehran’s refusal to negotiate directly with Washington.

The Vienna talks, which began in April 2021, aim to bring Iran back into compliance with the deal and facilitate a U.S. return to the agreement. The deal offered Iran sanctions relief in exchange for curbs on its nuclear program.

Iran’s Foreign Minister Hossein Amir Abdollahian reiterated during a visit to Beirut on Friday that he is optimistic about the prospects of an agreement, adding that it can also benefit all the countries in the region.

Former U.S. President Donald Trump unilaterally withdrew Washington from the deal in 2018 and reimposed sweeping sanctions on Tehran in line with his “maximum pressure” campaign against Iran.

A year after the U.S. quit the agreement, Iran responded by gradually lifting bans on its nuclear program. At the time Iran clearly announced that if the European signatories to the deal compensate Iran for the sanctions, Tehran will immediately reverse its measures.

Iran’s moves were in accordance to paragraph 36 of the JCPOA.