VIENNA (Reuters) – A collapse of the Iran nuclear deal would be a “great loss”, the U.N. atomic watchdog’s chief warned U.S. President Donald Trump on Monday, giving a wide-ranging defense of the accord and his agency’s work under it.

Trump has threatened to withdraw the United States from the accord between Tehran and six world powers, signed in 2015 before he took office, unless Congress and European allies help “fix” it with a follow-up pact. Trump does not like the deal’s limited duration, among other things. Continued reading.