Powell thought progress had been made in Geneva and that the deal proposed by Iran was “surprising," according to sources who spoke to the Guardian.
Two days after the talks ended, and after a date had been agreed for a further round of technical talks in Vienna, the US and Israel launched the attack on Iran.
"Powell’s presence at the talks, and his close knowledge of how they were progressing, was confirmed by three sources," reported the British media outlet.
"One source said he was in the building at Oman’s ambassadorial residence in Cologny, acting as an adviser, reflecting widespread concern about the US expertise on the talks represented by Donald Trump’s son-in-law, Jared Kushner, and Steve Witkoff, Trump’s special envoy on several issues."
Kushner and Witkoff had invited Rafael Grossi, the director general of the International Atomic Energy Agency (IAEA), to the Geneva talks to provide technical expertise.
However, Kushner would later claim that he and Witkoff had “a pretty deep understanding of the issues that matter in this”.
Nuclear experts would later say that Witkoff’s pronouncements on the Iranian nuclear programme were riddled with basic errors, according to the Guardian.
A former official who was briefed on the Geneva talks by some of the participants told the Guardian, “Witkoff and Kushner did not bring a US technical team with them. They used Grossi as their technical expert, but that is not his job. So Jonathan Powell took his own team.
“The UK team were surprised by what the Iranians put on the table,” the former official added. “It was not a complete deal, but it was progress and was unlikely to be the Iranians’ final offer. The British team expected the next round of negotiations to go ahead on the basis of the progress in Geneva.”
That next round of talks was due to take place in Vienna on Monday, 2 March, but never happened. The US and Israel had launched their all-out attack two days earlier.
UK officials have subsequently explained they were impressed that Iran was prepared for the deal to be permanent and, unlike the 2015 nuclear agreement, would not have cut-off dates, or sunset clauses ending the restrictions on its programme, reported the Guardian.
Iran had also agreed to down-blend the 400kg stockpile of highly enriched uranium under the supervision of the IAEA inside Iran. It agreed no stockpiles of highly enriched uranium would be built up in the future.
In the final session of the talks, Iran agreed to a three- to five-year pause on domestic enrichment, but the US, in the afternoon session, after consultations with Trump, demanded a 10-year pause.
In practice, Iran had no means to enrich domestically because of the bombing of its enrichment plants in 2015.
Iran had also made an offer of what the mediators described as an economic bonanza, with the US being given the chance to participate in a future civil nuclear programme.
In return, nearly 80 percent of the economic sanctions on Iran would have been lifted, including assets frozen in Qatar, a demand Iran made in the 2025 talks.
The Oman mediator believed the offer of zero stockpiling of highly enriched uranium was a breakthrough that meant an agreement was within reach.
"Accounts differ on whether Kushner left the talks, giving the impression Trump would welcome what had been agreed, or that the US negotiators knew it would take something massive to persuade Trump that war was not the best option. One diplomat with knowledge of the talks said: “We regarded Witkoff and Kushner as Israeli assets that dragged a president into a war he wants to get out of,” concluded the Guardian.
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