The U.S. wants Iran to end all uranium enrichment. The European nations have yet to make clear their position. The JCPOA limited Iran to enriching uranium up to 3.67% purity -- sufficient for civilian nuclear power purposes but below the 90% purity needed for use in a weapon.

Three European powers met with an Iranian minister to try to reopen negotiations over the limits of its nuclear activities.

Iran said it would continue nuclear talks with European powers after "serious, frank, and detailed" conversations on Friday, the first such face-to-face meeting since Israel and the U.S. bombed Iran last month.