Iran's new President Ebrahim Raisi named an anti-Western diplomat as foreign minister.
Raisi, a hardliner under Western sanctions over allegations of human rights abuses when he was a judge, was sworn into office on Aug. 5 with the Islamic Republic's clerical rulers facing growing crises at home and abroad.
The mid-ranking Shi'ite cleric replaced Hassan Rouhani as president after an election in June when most prominent rivals - including moderates and conservatives - were barred from standing.
Presenting his cabinet to parliament for an expected vote of confidence, Raisi chose Hossein Amirabdollahian as foreign minister and Javad Owji, an ex-deputy oil minister and managing director of the state-run gas company, as oil minister.
"Amirabdollahian is a hardline diplomat ... If the foreign ministry remains in charge of Iran's nuclear dossier, then obviously Tehran will adopt a very tough line in the talks," said an Iranian nuclear negotiator who asked not to be named.
Reports in semi-official Iranian media suggested that the Supreme National Security Council, which reports directly to hardline Supreme Leader Ayatollah Ali Khamenei would take over the nuclear talks in Vienna from the foreign ministry.
Amirabdollahian is believed to have close ties with Iran's elite Revolutionary Guards, Lebanon's powerful Hezbollah movement, and other Iranian proxies around the Middle East.