Diplomats say a report expected tomorrow from the UN nuclear agency will certify that Iran is ending some nuclear activities and limiting others under an interim deal with six world powers.
That first-step pact set the stage for ongoing talks on a deal to impose more nuclear restrictions on Iran in exchange for a full end to sanctions.
Iranian President Hassan Rouhani said today in Shanghai the two sides will "very likely" reach agreement by July, but talks could be extended.
The two diplomats' focus is on Iran's nuclear program. They demanded anonymity because they are not authorised to discuss confidential information.
Iran denies allegations it wants nuclear arms but says it's ready to reduce atomic activities if the sanctions end.
