After a long-running legal row over his appointment, Iran's deputy president for strategic affairs, Javad Zarif, announced his resignation on Monday.

In a detailed post on X, the former top diplomat said he had worked with dedication in President Masoud Pezeshkian's government over the past nine months but endured "the most vile insults, slanders, and threats directed at myself and my family" over the past six months.

He described this period as "the most bitter" of his 40-year political career, referencing the controversy surrounding his appointment as the country’s vice president.

Many of his critics argued that his appointment violated the Constitution, as his children — born in the US — are natural-born citizens of the US.

"Over the past four decades, I have endured countless insults and accusations for my small role in advancing national interests, from ending the imposed war to bringing the nuclear case to completion, and I have remained silent in the face of a flood of lies and distortions to protect the country's interests," he wrote in his resignation letter.

Zarif, who served as foreign minister for eight years under President Hassan Rouhani and played a key role in the 2015 Iran nuclear deal, said he was invited by the judiciary chief, who pointed to the country's current state and advised him to return to academia "to prevent further pressure on the government."

"I hope that with my departure, obstacles to the people's will and the government's success will be removed," Zarif said.

The former top diplomat had been under intense pressure from conservative political circles, which urged parliament to remove him from his government post.

Notably, Zarif, who had campaigned for Pezeshkian during the elections, also led the committee responsible for selecting candidates for various ministries and government departments.

There had been speculation about his resignation in the past too but he always dismissed them.

There has been no word so far from the president’s office on whether he will accept the resignation. But sources say the resignation will be accepted to prevent further pressure on the government.

On Sunday, Economy Minister Abdolnasser Hemmati was impeached by the parliament over mounting economic woes and depreciating national currency rial.