Under proposals discussed in rounds of talks in April, Iran would cap enrichment at 3.67%, in line with the JCPOA, all the sources said, including three Iranian officials. Tehran is also open to granting the IAEA expanded access to its nuclear sites, the Iranian sources said.

When the U.S. and Iran met for nuclear talks a decade ago, Israeli Prime Minister Benjamin Netanyahu railed against an emerging deal from the world’s most public stages, including in a fiery speech to Congress seen as a direct challenge to the Obama administration as it was wrapping up the talks.