The co-ordinator of talks in Vienna that aim to resurrect the <a href="https://www.thenationalnews.com/mena/2021/12/16/iran-will-not-accept-obligations-beyond-original-deal-says-foreign-minister/" target="_blank">2015 nuclear deal that Iran signed with world powers</a> has said officials have only weeks left to find an agreement as the seventh round of negotiations concluded. Senior EU official Enrique Mora said he hoped the talks would resume by the end of the year, but said a “very complex” task lay ahead. Iran’s nuclear envoy <a href="https://www.thenationalnews.com/mena/2021/12/13/irans-chief-negotiator-optimistic-after-important-evolution-in-vienna-talks/" target="_blank">Ali Bagheri Kani</a> said “good progress” was made this week in Vienna and added that there would be a break of a few days. China's representative said the talks will “resume hopefully before the end of the year”, while Russia's top official in Vienna said they would recommence soon. “We don't have months, we rather have weeks to have an agreement,” Mr Mora said. “There is a sense of urgency that is absolutely important if we want to really have success in these negotiations.” He added: “For the eighth round, we have a lot of work ahead, a very complex task, I have to say. Difficult political decisions have to be taken.” Gaps remain in Vienna nonetheless, and <a href="https://www.thenationalnews.com/world/europe/2021/12/14/iran-criticises-nuclear-deal-blame-game-at-vienna-talks/" target="_blank">Britain, France and Germany</a> this week warned Iran that time is running out. The 2015 deal Iran signed with the five permanent members of the UN Security Council as well as Germany and the EU offered Tehran sanctions relief in return for limits on its nuclear programme. But since US president Donald Trump unilaterally withdraw from the accord in 2018 and reimposed heavy sanctions on Iran, the country has repeatedly breached the terms of the deal. The seventh round of negotiations began late last month after a hiatus since June when presidential elections in Iran brought hardliner Ebrahim Raisi to power. He appointed Mr Kani as the new head of the Iranian delegation in Vienna. European negotiators this week expressed their frustration at the Iranian delegation's behaviour, accusing them of introducing a new series of demands in return for compliance with the accord. US diplomats have been involved indirectly in Vienna, with Mr Trump’s successor, US President Joe Biden, saying he wants a return to the deal.