Iran’s foreign minister and lead negotiator in nuclear talks with the United States has been ordered by the Islamic Republic’s Supreme Leader to stop shouting and yelling at Secretary of State John Kerry during negotiating sessions.

Iranian Foreign Minister Javad Zarif told his country’s state controlled media in a recent interview that Ayatollah Ali Khamenei has instructed him to stop yelling at Kerry and other top U.S. officials during the talks.

Reports about Zarif’s temper first emerged in the Iranian press last November, when the United States and Iran agreed to extend talks through June of this year.

Zarif is said to “frequently shout at Western diplomats” with such force that bodyguards have been forced to enter the negotiation room.

During one incident described by Iranian officials to the press, European Union Foreign Policy Chief Catherine Ashton, a chief western negotiator, admitted that Zarif had been shouting, and she had gotten used to it.

Abbas Araqchi, an Iranian diplomat who is also a member of the negotiating team, is reported to have said in an interview that during past negotiations in Geneva, Zarif “shouted” at Kerry and spoke to him in a manner “unprecedented” in the history of U.S. diplomacy.

In this March 30, 2014, photo U.S. Secretary of State John Kerry listens to a question at a news conference in Paris. AP/Jacquelyn Martin

Zarif appeared to cop to this behavior during a recent interview with the state-controlled Islamic Republic News Agency (IRNA), according to an independent translation of the report provided to the Washington Free Beacon.

Following reports that Zarif shouts at Kerry, Zarif was summoned to a meeting with Khamenei. He referred to this meeting during recent remarks made to a high school class, according to the IRNA.

Iran's Supreme Leader Ayatollah Ali Khamenei Reuters “‘Why you are yelling in negotiations? Smile and speak,’” he recalled the Supreme Leader saying. “‘Do not quarrel on the negotiation table, reason with them,’” Khamenei continued, citing a verse from the Quran that states “Go, both of you, to Pharaoh, for he has indeed transgressed all bounds.… But speak to him mildly; perchance he may take warning or fear [Allah].”

Zarif added that he begins each day by praying over six verses of the Quran before entering the nuclear discussions. He went on to say that U.S. sanctions no longer have an impact on Tehran.

“Doing business and trade with Iran had a huge reputational cost” for foreigners, but now the situation has changed, according to Zarif. “More sanctions on Iran makes U.S. isolated among its own friends.”

The State Department declined to comment on reports about the Iranian Foreign Minister’s conversations with the Iranian Supreme Leader.

Meanwhile, Khamenei, in a speech this week, said that Iran would impose its own sanctions on the West.

“If [there] is to be any sanction imposed, the Iranian nation too can impose sanction [on them] and it will do so,” Khamenei was quoted as saying by the Fars News Agency.

“Iran has also made it clear again and again that the U.S. should leave the Middle East and the Muslim world,” said Saeed Ghasseminejad, an Iranian dissident who is an associate fellow at the Foundation for Defense of Democracies.

“Both Zarif and Khamenei see themselves on a holy mission. They may have different assessments of what is the best way to reach their goal, which is to defeat the pharaoh of the time, but they have no doubt who is the pharaoh of the time: The West, the U.S., and Israel.”