Richard Nephew, who is known as the architect of Washington’s sanctions on Iran, has left the US negotiating team in Vienna over differences with chief US negotiator Robert Malley.

According to NBC News on Saturday, Nephew and Malley had a disagreement over the direction of the negotiations to revive the 2015 nuclear deal between Iran and world powers.

The report cited two people familiar with the matter as the source of the news but did not elaborate on the disagreement.

“Richard Nephew made important contributions to the team, where he served for nearly a year. He remains with the Department of State”, a State Department official said in a statement.

Back in March 2021, when Nephew was appointed as Malley’s deputy, some Iranian officials described it as proof of the Biden administration's “maliciousness.”

Iranian lawmaker Ahmad Naderi had said appointing the “architect of the oppressive sanctions” show that “Americans' hatred of Iran is not limited to Republicans or Democrats".

Iranian newspaper Vatan-e Emrooz had covered the news on its front page, depicting Nephew as Keanu Reeves from the movie The Devil's Advocate, with Biden replacing Al Pacino, who played the Devil.

Nephew, who is a non-resident Senior Fellow at the Brookings Institution, published a book about the sanctions in 2017, titled The Art of Sanctions: A View from the Field.