Iran “does not seem to be serious” about returning to the 2015 nuclear accord, US Secretary of State Antony Blinken said on Friday, as European allies voiced their “disappointment and concern” over differences with Tehran after <a href="https://www.thenationalnews.com/world/europe/2021/12/02/iran-presents-drafts-of-sanctions-plan-to-revive-nuclear-deal/" target="_blank">five days of talks in Vienna</a> closed out for the week. The seventh round of talks, due to resume next week, is the first with delegates sent by Iran's President Ebrahim Raisi aimed at <a href="https://www.thenationalnews.com/mena/2021/11/30/china-calls-on-us-to-lift-iran-sanctions-as-nuclear-talks-resume/" target="_blank">resuscitating the agreement </a>under which Iran limited its nuclear programme in return for relief from economic sanctions. But western powers suspect Iran is dragging talks out while simultaneously <a href="https://www.thenationalnews.com/mena/iran/2021/12/01/iran-increases-uranium-enrichment-despite-vienna-nuclear-deal-talks/" target="_blank">advancing its nuclear programme</a>. The International Atomic Energy Agency, the UN's nuclear watchdog, has said that Iran is continuing to enrich uranium to 20 per cent using advanced centrifuges in an underground site at Fordow, near Qom. The EU has said this is unacceptable and would put Tehran on the path to possessing "weapons grade" uranium which could be used in a nuclear device. The EU has called the work at Fordow, which was confirmed by the IAEA on January 4, "a very serious development and a matter of deep concern." “Iran right now does not seem to be serious about doing what's necessary to return to compliance, which is why we ended this round of talks in Vienna,” Mr Blinken said at a conference. “If the path to a return to compliance with the agreement turns out to be a dead-end, we will pursue other options,” he added, without elaborating. A State Department official told <i>The National </i>that the blame for the failure to reach a breakthrough lay with Iran. “They did not come to Vienna with constructive proposals. Iran’s approach this week was not, unfortunately, to try to resolve the remaining issues,” the official said. Diplomats from Britain, France and Germany, known as the E3, said significant gaps remained — and new ones had appeared — and accused Iran of retreating from compromises made during the previous six rounds of negotiations this year. In a briefing on Saturday, a senior State Department also accused Iran of reneging on earlier promises while increasing its demands. Iran came "with proposals that walked back anything - any of the compromises Iran had floated here in the six rounds of talks, pocket all of the compromises that others, and the US in particular, had made, and then asked for more," the official said, speaking on condition of anonymity. Separately, French President Emmanuel Macron said it was “probable that this round of negotiations, given the positions, does not succeed”. The talks, featuring Iran, China, the EU, France, Germany, Russia and the UK, were paused in June for the Iranian presidential elections that brought Ebrahim Raisi to power. The US has been involved in Vienna only indirectly. Ali Bagheri Kani was appointed as the new head of the Iranian delegation, which has been accused of making extreme demands in return for compliance with the 2015 accord. He said Iran's proposals were evidence “of our serious will to reach an agreement”, but also acknowledged the differences between the delegations. “I told them it's normal that we're not presenting documents and suggestions which correspond to your points of view,” he said on Friday after the talks. These include the removal of all sanctions that the US president at the time, Donald Trump, levied on Tehran when he withdrew from the deal in 2018. In response, Iran has <a href="https://www.thenationalnews.com/mena/iran/2021/12/01/iran-increases-uranium-enrichment-despite-vienna-nuclear-deal-talks/" target="_blank">repeatedly breached the terms of the accord</a>, but insists its nuclear programme is peaceful. Mr Trump’s successor, <a href="https://www.thenationalnews.com/mena/2021/11/01/jcpoa-talks-us-president-pledges-compliance-if-iran-does-the-same/">Joe Biden, has said America is willing to re-enter the deal</a>. The State Department official said that Iran's accelerating nuclear programme is “unprecedented". “That cannot continue,” the official said. “It will inevitably lead to a crisis.” On Friday, European diplomats involved in the talks issues a joint statement saying that Iran had made significant changes to a draft agreement that had been almost finalised by all sides. The E3 diplomats also expressed “disappointment and concern after thoroughly and carefully analysing Iranian proposed changes to the text negotiated during the previous six rounds". "Over five months ago, Iran interrupted negotiations. Since then, Iran has fast-forwarded its nuclear program. This week, it has back-tracked on diplomatic progress made," senior officials from France, Britain and Germany said a joint statement “Tehran is walking back almost all of the difficult compromises crafted after many months of hard work,” they said. The Iranian delegation had demanded “major changes” and the diplomats said it was “unclear how these new gaps can be closed in a realistic time frame". The delegations will now “return to capitals to assess the situation and seek instructions before reconvening next week to see whether gaps can be closed or not". “Our governments remain fully committed to a diplomatic way forward but time is running out.” EU diplomat Enrique Mora, who headed the meetings, said substantial challenges lay ahead and that “time is not unlimited; there is an obvious sense of urgency”. Pressed on what had been achieved this week in Vienna, Mr Mora said there was progress “in the sense that we have had a new Iranian delegation, they have engaged in negotiations with other delegations”. “We are incorporating, also, new policy sensitivities for the new Iranian delegations,” he said. “But again, the point of departure, the common ground is where we finished on June 20.”