Diplomats say talks on restoring the nuclear deal between world powers and Iran are entering their final stretch with Britain's top negotiator announcing on Friday: "We are close".
Stephanie Al-Qaq said she and her colleagues from France and Germany were returning to their capitals briefly to update political leaders but were "ready to return soon" to complete an agreement in Vienna.
The three European negotiators held another round of talks with Iranian officials on Friday after Ms Al-Qaq said diplomats "must now walk the last few metres" following 11 months of talks.
She said on Friday that a deal was “possible but not guaranteed” and called on negotiators to reach an agreement “before the diplomatic window closes”.
The EU’s top delegate in Vienna, Enrique Mora, said the talks between Iran, the UK, Germany, France, Russia, China, the EU and, indirectly, the US, were in their final stages but that “some relevant issues” were still open.
“Success is never guaranteed in such a complex negotiation,” he said late on Thursday. “Doing our best in the co-ordinator’s team. But we are definitely not there yet.”
Diplomats have described the talks as entering an endgame as they look to restore Iran’s compliance with the 2015 Joint Comprehensive Plan of Action and bring the US back into the fold.
The deal offered sanctions relief to Iran in exchange for limits on its nuclear activities to prevent it from developing an atom bomb.
Former US president Donald Trump pulled out of the deal and reimposed sanctions in 2018. Since then, Iran has openly flouted those limits by enriching and stockpiling uranium.
The International Atomic Energy Agency said this week that Iran’s enriched uranium stockpile had reached 15 times the limit set out under the JCPOA.
Washington has said that the US and Iran could reach a mutual understanding within days if Tehran’s negotiators “show seriousness”.
But western diplomats have signalled that the talks cannot drag on for ever because of the pace of Iran’s continuing nuclear activities.
The agency's director general, Rafael Grossi, will travel to Iran at the weekend after Tehran hinted that it wanted the UN agency to close investigations into undeclared nuclear sites.
Mr Grossi said this was a separate issue from the JCPOA talks and said he would not drop those investigations in order for the Vienna negotiators to reach a deal.
But he said he was optimistic that a solution could be found on this point without jeopardising the JCPOA.
