Israel and Iran are arch enemies and the Jewish state has always opposed the nuclear agreement, which it says could enable the Islamic republic to develop nuclear arms.
"Raisi's main challenge will be the economy. Eruption of protests will be inevitable if he fails to heal the nation's economic pain," said a government official.
"Everyone knows that, at this point, it will be necessary to wait for the new Iranian government," Rafael Grossi said.
The IAEA does not take any direct part in the negotiations but has been called on to verify any nuclear steps agreed in the talks and to continue inspections in the country.
Blinken reiterated support for returning to the nuclear accord, with which UN inspectors said Iran was complying before Trump pulled out the United States.
Tehran's oil exports have risen since late 2020, despite US sanctions toughened under US President Donald Trump. Joe Biden's administration took office in January pledging to rejoin Iran's nuclear deal with world powers, which Trump had quit.
"China and Iran are carrying out normal economic and trade cooperation, including energy, within the framework of international law, and the relevant cooperation is reasonable and legitimate," the spokesperson said.
The comments by Ambassador Rayed Krimly, head of policy planning at the ministry, were the first public confirmation from Riyadh that the rivals - who severed ties in 2016 - were holding direct talks.
"We hope they prove successful, but it is too early, and premature, to reach any definitive conclusions. Our evaluation will be based on verifiable deeds, and not proclamations."
The step will bring Iran closer to the 90 percent purity threshold for military use and shorten its potential "breakout time" to build an atomic bomb -- a goal the Islamic republic denies.
Iran’s move to enrich uranium up to 60% purity is a response to the sabotage at its key nuclear facility, President Hassan Rouhani said on Wednesday, adding the Islamic Republic had no intention of building a nuclear weapon.
"We have no problem with returning to implementing our JCPOA commitments," Mohammad Javad Zarif said, referring to the deal with major powers, which Washington quit in 2018.
Rouhani inaugurated the three cascades of 164 IR-6 centrifuges, 30 IR-5 and another 30 IR-6 devices at Iran's Natanz uranium enrichment plant in a ceremony broadcast by state television.
On Wednesday, diplomats from major powers met separately with leaders from Iran and the United States, to discuss how to bring both countries back into the fold of the nuclear deal, which was abandoned three years ago.
The United States is prepared to remove sanctions on Iran to resume compliance with the Iran nuclear deal, including those that are inconsistent with the 2015 pact.
Iran will not stop its 20% uranium enrichment before the United States lifts all sanctions, Iranian state TV quoted an unnamed official as saying on Tuesday, after a U.S. media report said Washington would offer a new proposal to jump-start talks.
President Joe Biden’s nominee to become the Pentagon’s top policy adviser faced relentless Republican criticism on Thursday over his support for the Iran nuclear deal, in a confirmation hearing that could foreshadow bigger fights over Biden’s national security agenda.
Iran will “immediately reverse” actions in its nuclear programme when U.S. sanctions are lifted, its foreign minister said on Friday, reiterating Tehran’s position on Washington’s offer to revive talks.
The Biden Administration said on Thursday it was ready to revive a 2015 agreement between Iran and world powers that former president Donald Trump abandoned in 2018 before reimposing sanctions on Iran.
Director General Rafael Mariano Grossi will visit Tehran on Saturday for discussions with senior Iranian officials in order to find a mutually agreeable solution for the IAEA to continue essential verification activities in the country.