VIENNA (Dispatches) — Signatories of a 2015 nuclear deal with Iran ended a fourth round of high-level talks Friday aimed at bringing the U.S. back to the accord, with calls for further efforts to work out the major stumbling blocks.
The talks began in early April and Russian delegate Mikhail Ulyanov tweeted following Friday’s meeting that "the participants agreed on the need to intensify the process.”
"The delegations seem to be ready to stay in Vienna as long as necessary to achieve the goal,” he wrote.
The U.S. pulled out of the landmark 2015 deal in 2018 after then-President Donald Trump said the pact needed to be renegotiated. The deal had promised Iran economic incentives in exchange for curbs on its nuclear program, and the Trump administration reimposed heavy sanctions on the Islamic Republic in an unsuccessful attempt to bring Tehran into new talks.
Iran reacted by reducing its compliance with the deal, by enriching uranium to a greater purity and using more advanced centrifuges.
U.S. President Joe Biden claims he wants to rejoin the deal, known as the Joint Comprehensive Plan of Action, or JCPOA, but refuses to undo any of the former administration’s wrongs.
Iran has said it is prepared to reverse all of its remedial measures taken in response to the other sides’ violations but that Washington must remove all sanctions imposed under Trump.
On the other side, the Associated Press wrote, is the question of what Iran’s return to compliance would look like.
"Delegates to the Vienna talks concede, for example, that Iranian nuclear scientists cannot unlearn the knowledge they acquired in the last three years, but it is not clear whether Iran’s new centrifuges would need to be destroyed, mothballed and locked away, or simply taken offline,” it said.
On Thursday, Press TV said it had learned that the U.S. and the Europeans apparently wanted Iran to destroy its new-generation centrifuges in return for a temporary suspension of some of the sanctions related to the nuclear deal.
This is while under the JCPOA, Iran’s advanced centrifuges — including IR-4, IR-6 and IR-9 — must be stored away under the supervision of the International

 Atomic Energy Agency (IAEA), and not destroyed, the network said.
"Not only will Iran not give in to the excessive demands of the Westerners, but in case of insistence on the part of the other side, the possibility of the JCPOA, and not just the negotiations in Vienna, unraveling altogether will be real,” Press TV said, citing its learning from the ongoing negotiations.
The new demands have been made while the U.S. has not even agreed to remove all the JCPOA-related sanctions, the English-language television said.
Because the U.S. is currently out of the deal, there was no American representation at the talks. Diplomats involved are shuttling between the Iranian side and a delegation from Washington elsewhere in Vienna.
Between the high-level meetings, expert groups have been meeting to try and come up with solutions to the outstanding issues.
The Associated Press cited it described as a senior U.S. official as saying that it remains possible to reach an agreement before Iran’s June presidential election.
Iran’s delegate to the talks, Deputy Foreign Minister Abbas Araqchi, told IRNA late Thursday that his team was trying to reach an agreement as soon as possible but would not act in haste and would act in Iran’s national interests.
"We are on a specified path about which there are, fortunately, agreements, but there are serious obstacles in the way as well,” Araqchi said.
Heading into the talks, Ulyanov tweeted that he saw positive signs from the Iranian minister’s statements.
"The head of the Iranian delegation is cautious in his assessment of the current state of affairs at the Vienna talks (very similar to assessments of the U.S. colleagues),” he tweeted. "But both #Iran and #U.S. refrain from pessimistic conclusions. This seems to be not a bad sign.”