Iran will accept a nuclear deal under which United Nations sanctions could be reimposed in the event of non-compliance, so long as Tehran enjoys similar protections, a senior negotiator was quoted as saying.
Last week, Western officials told Reuters that six world powers, negotiating with Iran towards a June 30 deadline, had agreed on a so-called "snapback" under which UN sanctions would be restored if Iran broke the terms of any eventual deal.
"The deal will be arranged such that if either side feels that the other is in breach of its obligations, it can turn back and resume the activities it had before the deal," Tehran's chief nuclear negotiator, Abbas Araqchi, was quoted as saying by state news agency IRNA on Sunday.
"We absolutely do not trust the other side, and they do not trust us."
Araqchi did not provide details on how to implement either side's guarantee.
Iran resumed negotiations in Vienna last week with the United States, France, Britain, Germany, Russia and China after reaching a framework accord on April 2.
Despite significant progress, several major disputes remain to be resolved including access for UN nuclear inspectors to Iranian military sites and the pace and timing of sanctions relief for Tehran.
Araqchi said the main text of a deal was likely to exceed 20 pages, with an additional 40-50 pages of annexes, adding that negotiators were scrutinising every word.