The Treasury Department announced the sanctions on Wednesday, after declining earlier this month to blacklist the outspoken diplomat. The move comes at a critical time for US/Iran relations, with the US currently putting together a multinational maritime mission to protect shipping traffic in the Persian Gulf, and combat “Iranian aggression.”

Sanctioning Tehran’s top diplomat could permanently shut the door on a diplomatic resolution to the current standoff, and reinforce the Iranian government’s belief that the Americans “are not seeking dialogue,” as a Foreign Ministry spokesman stated on Monday.

Diplomatic repercussions aside, the sanctions are unlikely to trouble Zarif, who said he has no property or bank accounts outside Iran.

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