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.

Donald Trump threatened to strike Iran again and reiterated his claims that the U.S. airstrikes conducted as part of Operation Midnight Hammer last month "obliterated" the country's nuclear sites.Quoting Iranian Foreign Minister Abbas Araghchi,

Iranian and European diplomats have met in Istanbul to embark on the latest drive to unpick the deadlock over Tehran’s nuclear program.