Senior officials from Iran and Europe's top three powers are due to meet in Geneva on Tuesday to discuss the Westerners' demand that Iran revive nuclear inspections and diplomacy or face the reimposition of sanctions that were lifted under a 2015 deal.
France, Britain and Germany, known as the E3, have long threatened to trigger the "snapback" of sanctions at the United Nations Security Council by October 18, when a now largely defunct nuclear deal struck 10 years ago between Tehran and major powers expires, Reuters said.
They have more recently said they plan to decide by the end of August unless Iran offers concessions that could convince them to hold off for a short time, often referred to as an extension. Talks are tense as Iran is furious at the bombing of its nuclear facilities by the US and Israel, the E3's allies.
"We are going to see whether the Iranians are credible about an extension or whether they are messing us around. We want to see whether they have made any progress on the conditions we set to extend," one E3 official said.
Those conditions are the resumption of inspections, including accounting for Iran's large stock of enriched uranium, and engaging in diplomacy, including with the United States. Iran has repeatedly ruled out direct talks with Washington.
Israel and the United States have said they needed to strike Iran's uranium enrichment sites because it was making such rapid advances towards being able to produce a nuclear weapon.
Tehran denies any intent to develop atomic bombs.
Iran has been enriching uranium to up to 60% purity, a short step from the roughly 90% of weapons-grade, and had enough material enriched to that level, if enriched further, for six nuclear weapons before the strikes started on June 13.
Actually producing a weapon would take more time, however, and the International Atomic Energy Agency has said that, while it cannot guarantee Tehran's nuclear program is entirely peaceful, it has no credible indication of a coordinated weapons program in Iran.
While Iran's enrichment facilities have been badly damaged or destroyed, Iran has not granted the IAEA access to them since they were attacked, arguing that it is not safe for inspectors. The status and whereabouts of Iran's large stockpile of enriched uranium are also unclear.
"Due to the damage to our nuclear sites, we need to agree on a new plan with the agency — and we’ve conveyed that to IAEA officials," one Iranian official said.
Western officials have said they suspect Iran has returned to negotiating tactics aimed at buying time and dragging talks out. The E3 will aim to determine in their talks on Tuesday whether that is now the case.
Tehran has warned of a "harsh response" if sanctions are revived.
