The U.S. and Iranian foreign ministers last week discussed the importance of carrying out the November 24 Iran nuclear deal after Washington blacklisted 19 companies, people and vessels for dealing with Tehran, a U.S. official said on Monday.
The U.S. sanctions, imposed under existing U.S. law, drew criticism from Iranian officials and raised questions about the November 24 agreement under which Iran agreed to curb its nuclear program for six months in exchange for limited sanctions relief.
"They discussed the importance of moving forward" on carrying out the agreement "and of maintaining a constructive atmosphere as the negotiations continue," the U.S. official said. "The conversation was focused on the way forward."
Under the November 24 agreement, the United States committed not to impose new sanctions on Iran. U.S. officials said they had not violated the deal in blacklisting the companies, vessels and individuals under existing law and said their commitment under the deal referred to not imposing sanctions under new laws.
The U.S. State Department said it told Iranian negotiators during talks before the November 24 deal that it would enforce existing U.S. sanctions laws and gave Iranian officials a general advance warning about last week's blacklisting action.
Some Iranian officials, however, argued that the United States had violated the spirit of the deal, which was struck between Iran and six major powers and which is designed to provide time to try to negotiate a comprehensive agreement.
The U.S. State Department official, who spoke on condition of anonymity, said U.S. Secretary of State John Kerry had spoken to Iranian Foreign Minister Javad Zarif by telephone from his aircraft as the chief U.S. diplomat flew from Israel to Vietnam.
It was unclear exactly when the conversation took place, but Kerry was due to leave the Middle East late on Friday and to arrive in Ho Chi Minh City, Vietnam on Saturday.
The latest U.S. sanctions -- known in Washington jargon as "designations" -- were imposed on Thursday.