The US said Monday it was still ready to meet Iran and was not "dogmatic" about how, after Tehran rejected an EU-proposed gathering.
"We remain ready to engage in meaningful diplomacy to achieve a mutual return to compliance" in a 2015 nuclear deal, State Department spokesman Ned Price said.
President Joe Biden's administration supports a return to the 2015 nuclear accord from which former president Donald Trump withdrew, and on February 18 said it was willing to meet Iran in a meeting proposed by the EU.
The meeting would involve the other signatories of the 2015 agreement – Britain, China, France, Germany and Russia.
But Iran said on Sunday that the timing was not "suitable", as it insisted that the US first lift sanctions imposed by Mr Trump.
"As we have made clear, the United States is prepared to meet Iran to address the way forward on a mutual return to compliance," Mr Price said.
"We're not dogmatic about what form that takes. What we are dogmatic about is the underlying commitment that this administration broadly has: that Iran cannot be allowed to acquire a nuclear weapon."
Iran has insisted that sanctions imposed by Mr Trump, including a sweeping ban on its oil exports, should be removed before it reverses moves it has made away from nuclear compliance.
Manikarnika: The Queen of Jhansi
Director: Kangana Ranaut, Krish Jagarlamudi
Producer: Zee Studios, Kamal Jain
Cast: Kangana Ranaut, Ankita Lokhande, Danny Denzongpa, Atul Kulkarni
Rating: 2.5/5
Innotech Profile
Date started: 2013
Founder/CEO: Othman Al Mandhari
Based: Muscat, Oman
Sector: Additive manufacturing, 3D printing technologies
Size: 15 full-time employees
Stage: Seed stage and seeking Series A round of financing
Investors: Oman Technology Fund from 2017 to 2019, exited through an agreement with a new investor to secure new funding that it under negotiation right now.
UAE currency: the story behind the money in your pockets
UAE currency: the story behind the money in your pockets
UAE currency: the story behind the money in your pockets
SPAIN SQUAD
Goalkeepers Simon (Athletic Bilbao), De Gea (Manchester United), Sanchez (Brighton)
Defenders Gaya (Valencia), Alba (Barcelona), P Torres (Villarreal), Laporte (Manchester City), Garcia (Manchester City), D Llorente (Leeds), Azpilicueta (Chelsea)
Midfielders Busquets (Barcelona), Rodri (Manchester City), Pedri (Barcelona), Thiago (Liverpool), Koke (Atletico Madrid), Ruiz (Napoli), M Llorente (Atletico Madrid)
Forwards: Olmo (RB Leipzig), Oyarzabal (Real Sociedad), Morata (Juventus), Moreno (Villarreal), F Torres (Manchester City), Traore (Wolves), Sarabia (PSG)