Foreign Minister of Iran Mohammad Javad Zarif stepped down on Monday after announcing his resignation on Instagram, Iranian media reports.

“I am apologizing you for all the shortcomings...in the past years during my time as foreign minister ... I thank the Iranian nation and officials,” he wrote on his Instagram page jzarif_ir.

Zarif played an important role in striking a 2015 nuclear deal between Iran and six world powers.

But he came under attack by anti-Western hardliners after the United States pulled out of the agreement last May and reimposed sanctions that were lifted under the deal.

Iran’s semi-official Tasnim news agency said “some sources have confirmed Zarif’s resignation”, but it is not clear yet whether President Hassan Rouhani would accept it.