Iran's Foreign Ministry said Tuesday that Deputy Foreign Minister Abbas Araghchi, who had been leading the country's negotiation team in its indirect talks with the United States on reviving a 2015 nuclear deal, is stepping down.

Named as his successor as deputy foreign minister is Ali Bagheri Kani, a hard-line diplomat who has been critical of the deal under which Iran had agreed to curb its nuclear activities in exchange for the lifting of sanctions.

Iranian Deputy Foreign Minister Abbas Araqchi speaks over the Iran nuclear deal during a press conference in Tehran in August 2015. (Anadolu Agency/Getty/Kyodo)

Araghchi, also known for his friendly ties with Japan as a former ambassador to the country, was named an adviser to new Foreign Minister Hossein Amir Abdollahian, according to the ministry.

Indirect talks between the United States and Iran were suspended in June. While the new administration of ultra-conservative President Ebrahim Raisi has indicated plans to continue the talks, it remains unclear what could come of them even if they were resumed.

Bagheri was a senior official of Iran's Supreme National Security Council handling nuclear talks under the government of anti-U.S. hard-line President Mahmoud Ahmadinejad, who served from 2005 to 2013. The talks made little progress then, deepening rifts between Iran, and the United States and Europe.

A landmark nuclear pact with six major powers -- Britain, China, France, Germany, Russia and the United States -- was eventually struck in 2015.

But U.S. President Joe Biden's predecessor Donald Trump criticized the deal as flawed and pulled the United States out of it in May 2018. Iran countered the U.S. move by increasing its nuclear activities beyond the limits set in the deal.

Araghchi, ambassador to Japan from 2008 to 2011, played a major role when Japanese Prime Minister Shinzo Abe visited Iran's capital Tehran and Raisi's predecessor Hassan Rouhani visited Japan, both in 2019.

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