Iran has long insisted its program is peaceful, though it is the only non-nuclear-armed nation enriching uranium at that level. The U.S., the IAEA and others say Iran had a nuclear weapons program up until 2003.

The clash over Iran's nuclear program is escalating, with U.S. sanctions and Europe's snapback threat putting Tehran under maximum pressure.

Iranian Foreign Minister Abbas Araqchi and his French, British and German counterparts agreed on Friday to resume talks next week on nuclear issues, Iranian state media reported, as a threat by the European powers to reimpose sanctions looms.