The U.S. special envoy for Iran, Brian Hook, is holding talks on Iran with French, German, and British top diplomats in Paris on June 27.
Talks come amid efforts by European countries to try to save a landmark 2015 nuclear deal struck by world powers with Tehran.
European signatories of the accord want to avoid a further escalation in tensions between the United States and Iran and are trying to convince Tehran not to leave the deal, which U.S. President Donald Trump pulled out of last year.
Iran's UN ambassador on June 26 urged Britain, France, and Germany to take 'timely' practical steps to preserve the agreement, 'which is now in critical condition.'
Tehran has said it will break out of the nuclear deal's limit on its stockpiles of low-enriched uranium by June 27, following the reimposition of sanctions by Washington.
Diplomats told Reuters on June 27 that Iran is still short of the maximum amount of low-enriched uranium it is allowed to have under its deal with major powers, according to the latest data from UN nuclear inspectors.
However, the diplomats, who spoke on condition of anonymity, said Iran is on course to reach that limit at the weekend, and that makes it unlikely Iran will follow through on its threat.
The 2015 agreement, which lifted most international sanctions against Iran in exchange for restrictions on its nuclear activities, is aimed at extending the time Iran would need to produce an atomic bomb.
Based on reporting by AP and Reuters
Copyright (c) 2018. RFE/RL, Inc. Republished with the permission of Radio Free Europe/Radio Liberty, 1201 Connecticut Ave NW, Ste 400, Washington DC 20036