Iran would be ready to resume talks on the nuclear deal with the US and other western powers if they provide a “clear signal” that sanctions will be lifted within a year, a senior Iranian conservative figure and a potential presidential candidate has said.

“They can announce and reassure us that all sanctions imposed after the JCPOA [the 2015 nuclear accord] would be lifted in less than one year and tell us to go and negotiate this process,” Mohsen Rezaei, who led the Revolutionary Guards for 16 years, said in an interview with the Financial Times. These comments are the clearest indication yet of the Islamic republic’s willingness to engage with the US.

Donald Trump pulled the US out of the nuclear deal with global powers in 2018, imposing the toughest sanctions yet on the republic as his administration sought to secure a new deal that included Iran’s regional and military policies. President Joe Biden is willing to return to the deal provided Iran, which has rolled back most of its commitments under the accord, also returns to full compliance. Iran said the US should return to the nuclear agreement unconditionally because it was the one that left it.

“We have to see every month during the talks that some sanctions which are of urgency to us are being lifted,” Rezaei said, outlining Iran’s most detailed demands yet for a return to the discussions. “For instance, sanctions on financial transactions and restrictions that European banks have imposed should be lifted in the first month. Oil exports are also among our top priorities.”

He said other US moves such as, for example, helping unfreeze billions of dollars of Iranian money held in overseas banks as an encouragement to start talks, would be akin to giving the republic “a candy”.

Iran’s foreign ministry spokesman, Saeed Khatibzadeh, said “all foreign policy issues are conveyed only through official channels” and that “clearly” Mohammad Javad Zarif, the country’s foreign minister “is in charge” not Mr Rezaei “who has no direct or indirect responsibility” in this regard.