DUBAI (Reuters) - Iran said on Saturday it believes a reinstatement of its 2015 nuclear deal with major world powers is possible but warned that Tehran “will not negotiate forever”.

"Out of a steadfast commitment to salvage a deal that the US tried to torpedo, Iran has been the most active party in Vienna, proposing most drafts," Iranian Foreign Ministry spokesman Saeed Khatibzadeh said on Twitter, referring to talks aimed at reviving the nuclear deal.