A report published Tuesday erroneously said that Iranian President Hassan Rohani had rejected the resignation of Foreign Minister Mohammad Javad Zarif. The story was later retracted, with Reuters explaining that it had mistakenly cited an Instagram account run by the president's supporters and not his official page.

>> Zarif’s exit is good news for Iran’s radicals, bad news for the West | Analysis

Zarif said Tuesday he hoped his sudden resignation would reinforce the position of his fellow diplomats, hinting that a dispute with the security apparatus and hard-liners led to a "deadly poison for foreign policy."

Zarif's move sent shockwaves through Iran, where tensions are already running high over America's withdraw from the nuclear deal he helped negotiate with Rohani.

An ally of Zarif said his resignation was motivated by criticism of the nuclear accord, under increasingly intense fire in Iran since the United States abandoned it last year.

"There were closed-door meetings every week, where top officials were bombarding him with questions about the deal and what will happen next and so on," a Zarif ally told Reuters on condition of anonymity. "He and his boss (Rohani) were under a huge amount of pressure."

Since the United States walked out of the nuclear deal and reimposed sanctions last year, Rohani has had to explain why Iran has continued to abide by its restrictions while reaping virtually none of the foreseen economic benefits.

Iran's Foreign Ministry reiterated that Rohani had not accepted Zarif's resignation, rejecting reports in the media.