Iranian and United States lead negotiators were in Doha Tuesday as Qatar expressed hope that talks would “culminate in positive results that contribute to revival of JCPOA.” 

In a statement, the Qatari Foreign Ministry said the talks to revive the 2015 nuclear deal – the JCPOA, Joint Comprehensive Plan of Action – would be coordinated by the European Union.

Ali Bagheri-Kani, leading the Iranian delegation, arrived in Doha Tuesday morning. Welcoming him, Tehran’s ambassador Hamidreza Dehghani, tweeted, "Without any prejudice and expression of unrealistic pessimism or optimism, I wish them success in carrying out their important mission.”

United States special envoy Robert Malley met Tuesday with Qatar's Foreign Minister Mohammed bin Abdulrahman Al Thani. The US embassy said they discussed “the strong partnership and our joint diplomatic efforts to address issues with Iran.”

US National Security Advisor Jake Sullivan reiterated Monday that restoring the JCPOA was the best way to preclude any possible Iranian path to a nuclear weapon, and reiterated that Washington put the onus on Tehran to make the necessary moves. “There is a deal available on the table to Iran, and it’s up to Iran to decide whether or not it wants to take it,” Sullivan said.

Some analysts portray the talks – which, although US and Iran still talk indirectly, are separate to stalled Vienna talks between Iran and six world powers – as the last chance for Washington and Tehran to revive the JCPOA.