Mohammad Javad Zarif, deputy for strategic affairs to President Masoud Pezeshkian, announced his resignation in protest over the proposed cabinet's composition.
In a statement, Zarif revealed that only three of the 19 ministers introduced were the first choices recommended by a committee responsible for candidate selection.
According to Zarif, ten of the proposed ministers were not on the council's list at all.
"I am not satisfied with the outcome of my work and I am ashamed that I could not achieve the expert opinion of the committees and the inclusion of women, youth, and ethnic groups as I had pledged," Zarif said.
He apologized to the Iranian people for his inability to navigate the complexities of domestic politics and announced his intent to return to academia.
Zarif's resignation has intensified scrutiny of Pezeshkian's cabinet choices.
On Sunday, President Pezeshkian presented his list of 19 ministers to the Iranian parliament for a vote of confidence.
The list, however, has faced widespread criticism, especially from Zarif's allies during the elections.
The proposed cabinet has drawn attention for its lack of diversity, having only one woman, no Sunni ministers, and no representation from ethnic minorities.
Additionally, there is a strong presence of individuals with security and military backgrounds, which has raised concerns.
Azar Mansouri, head of the Reform Front, condemned the proposed cabinet, saying, "One should not expect miracles from this government, especially considering that more than 80 percent of the country's power is in the hands of other entities."
The nominated cabinet's average age of 59.7 contradicts Pezeshkian's earlier promise that 60 percent of ministers would be under 50.
Key nominations include Abbas Araghchi, Minister of Foreign Affairs, who previously served as Zarif's deputy during Hassan Rouhani's presidency.
Esmail Khatib, nominated as Minister of Intelligence, has a controversial record, including oversight during the deadly explosion in Kerman earlier this year.
Javad Imam, a spokesperson for the Reform Front, voiced his concerns about the nominated cabinet, saying it continued the "control of the military and militias over politics."
The Reform Front criticized the government's approach, questioning the necessity of elections if the aim was to maintain the status quo.
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