Iran Foreign Minister Javad Zarif in Shock Resignation

Iranian Foreign Minister Mohammad Javad Zarif has submitted his resignation, announcing the decision in a brief Instagram post, although Iran Press has made the claim that Zarif's resignation has yet to be accepted by President Hassan Rouhani.

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"Many thanks for the generosity of the dear and brave people of Iran and its authorities over the past 67 months," he wrote on his Instagram page jzarif_ir, according to a Reuters translation.

He gave no specific reasons for his decision, but cited an "inability to continue serving."

"I sincerely apologise for the inability to continue serving and for all the shortcomings during my service. Be happy and worthy," his post read.

Meanwhile, Iran Press reported that, "the Head of Presidential Office Mahmoud Vaezi in a message rejected news reports that Foreign Minister Mohammad Javad Zarif's resignation had been accepted by President Rouhani."

Zarif played an important role in striking a 2015 nuclear deal between Iran and six world powers, but he came under attack by Iranian hardliners after the United States pulled out of the agreement last May and reimposed economic sanctions on some of the country's key industries, reported the Middle East Eye.

Sina Toossi, research associate at the National Iranian American Council (NIAC), noted the "striking and strange" nature of the announcement on Instagram.

He said the use of a popular and uncensored social media platform in Iran may have been a deliberate attempt for the news to reach the public directly.

"It could be a kind of calculated play where Zarif is submitting his resignation in a public way on Instagram... If Rouhani does not accept his resignation, if indeed he does not resign, he could come back empowered," Toossi told MEE.

"He offered his resignation; there was a huge outcry. He could come back stronger in his position."

But if the foreign minister does reign, Toossi said, it would be a major shift in the domestic balance of power away from the "moderate, pragmatic, reformist faction that Zarif embodies, especially on foreign policy".

Barbara Slavin, director of the Future of Iran Initiative at the Atlantic Council, echoed Toossi's comments on the Instagram announcement.

"A lot of Iranians are on Instagram, and of course his announcement was made in Farsi. If he wanted to reach Iranian public opinion, this was a very effective way to do it," Slavin told MEE.

In a speech given in Munich, Germany last week, Zarif defended Iran against hostile rhetoric from members of the Trump administration and condemned Washington for pulling out of the 2015 nuclear deal.

"In spite of all the ignorant hate-speech by American officials, let me remind you that we Iranians are proud to be the inheritors of a great civilisation," Zarif said in the speech, a transcript of which was shared by Iran's foreign ministry.

"The entirety of humanity is today riding in the same boat and we either sail together; or sink together," he said.