Nuclear talks between Iran and world powers formally resumed in Vienna on Thursday and ended within an hour, though Russia's envoy to the talks said the meeting was productive.
"The meeting of the Joint Commission is over. It was rather short and constructive. The participants observed a number of important commonalities in their positions, including with regard to the need to finalize the Vienna Talks on restoration of JCPOA successfully and swiftly," wrote Russian envoy Mikhail Ulyanov on Twitter.
Iran's top negotiator, Ali Bagheri Kani, meanwhile, said he was sticking to the positions Tehran set out when nuclear talks broke off last week. European Union and Russian envoys called for more urgency as world powers resumed negotiations in Vienna.
"Iran underlined that it is seriously continuing the talks based on its previous position," the Iranian negotiator told reporters, according to the Reuters news agency.
"Iran is serious about reaching an agreement if the ground is paved (towards a deal)...The fact all sides want the talks to continue shows that all parties want to narrow the gaps," he added.
Enrique Mora, the European Union's coordinator for the talks, said the sides "don't have all the time in the world".
"What I felt this morning was from...all delegations a renewed sense of purpose in the need to work and to reach an agreement on bringing the JCPOA back to life," Mora said.
Indirect negotiations between the US and Iran on a return to the nuclear deal resumed in Vienna last week, after a six-month hiatus following the election in June of Iranian President Ebrahim Raisi.
US Secretary of State Antony Blinken last Friday criticized Iran and said it is not serious about reviving the 2015 nuclear deal.
“What we’ve seen in the last couple of days is that 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,” Blinken said during the Reuters Next conference, after the latest round of indirect talks adjourned.
He warned that the United States would not let Iran drag out the process while continuing to advance its nuclear program and stressed that Washington will pursue other options if diplomacy fails.
Iran has repeatedly demanded that the US lift sanctions imposed on Iran and also reassure Iran it will not abandon the deal again as a precondition for its returning to compliance with the deal.
US officials have said that while they prefer the diplomatic route to reach an agreement with Iran, there are other options on the table should that fail.