Although he has never been elected or appointed to office, Mojtaba Khamenei, Iranian leader Ali Khamenei's 54-year-old son, has assumed the de facto role of his father's successor.
His actions, somewhat behind the scenes in the past, have become increasingly overt.
In the past, officials and commanders of the Islamic Revolutionary Guard Corps (IRGC) would generally refrain from referring to Mojtaba Khamenei by name or from quoting him.
Recently, however, this has changed and Khamenei's second son has risen to prominence even though the leadership of the Islamic Republic follows the regulations of the Guardianship of the Jurist and, per the regime's constitution, is not hereditary.
According to the constitution, all supreme leaders (following Rouhollah Khomeini) are to be elected by the Assembly of Experts who are elected by Iranian voters to eight-year terms.
Mojtaba has his father's ear and, as a result, vast control over decision-making in the IRGC and its external arm, the Quds Force (IRGC-QF).
Though his decisions and actions have reportedly even angered IRGC commanders, his father's carte blanche has granted him enough power to carry on over the objections of regime officials.
Criticism of Mojtaba's decisions
A leaked confidential document detailing the contents of a secret meeting among IRGC commanders, intelligence officials and Ali Khamenei on January 3 demonstrates that IRGC officials who were in charge of the crackdown on recent anti-regime protests were dismayed at the decisions Mojtaba had made.
Yadollah Bouali, commander of the Fars province's IRGC-affiliated Fajr Force, criticised forces under Mojtaba's command in the meeting.
"These forces had disrupted the country's security structure," Bouali said.
Bouali's remarks show the younger Khamenei has a hand in appointing and selecting commanders of the IRGC and intelligence forces in Iran at a sensitive time for the regime -- when it is fearful of its demise.
The pressure Mojtaba allegedly exerted, which resulted in the replacement of security and military forces, could bring "catastrophic" consequences, Bouali said in the meeting.
But the elder Khamenei has evidently made his preferences clear: he wants his son at the helm within the IRGC -- arguably the most powerful body in the country.
According to some reports, Mojtaba was also behind the decision to overhaul the IRGC's intelligence apparatus by removing Hossein Taeb, the IRGC intelligence chief and a close confidant, after 13 years in the post.
In June, Taeb was replaced by Gen. Mohammad Kazemi, who formerly headed the IRGC counter-intelligence agency known as the Intelligence Protection Organisation.
Iran's Sharq daily described the replacement as "a political earthquake", as have many analysts.
Taeb, a mid-ranking cleric widely described as a "petrifying figure", was at the helm of the IRGC's intelligence division since its inception.
An Iran-based political analyst who did not wish to be named said some intelligence officials and IRGC figures did not agree with Taeb's removal but that the order "had come from above".
The decision was reportedly made by Mojtaba and was therefore final, the analyst said.
It has become a given that a decision made by Mojtaba is equivalent to a decision made by his father, he told Al-Mashareq.
Role in fraudulent elections
Mehdi Karroubi, a reformist cleric and politician, made one of the first public mentions of Mojtaba's role in Iranian politics after the disputed presidential elections of 2009.
Karroubi, who ran against incumbent Mahmoud Ahmadinejad and reformist Mir-Hossein Mousavi -- but was defeated -- has been under house arrest since 2009.
The disputed election results ignited the uprising known as the Green Movement in Iran, ending with the regime's severe crackdown on the protests and the house arrest of both Karroubi and Mousavi.
Karroubi spoke out against the results and in an open letter to Khamenei mentioned that his son, Mojtaba, favoured Ahmadinejad, implying that the younger Khamenei had a hand in the decision to keep Ahmadinejad in power.
Other than his role in Iran's politics, Mojtaba has been accused of exporting terrorism and playing a role in leading the regime's pursuit of its expansionist agenda.
On November 4, 2019, he came under sanctions by the US Treasury Department.
"Mojtaba Khamenei, the second son of the Supreme Leader, is designated today for representing the Supreme Leader in an official capacity despite never being elected or appointed to a government position aside from work in the office of his father," the US Treasury said in a statement.
"The Supreme Leader has delegated a part of his leadership responsibilities to Mojataba Khamenei, who worked closely with the commander of the IRGC-QF and also the Basij Resistance Force (Basij) to advance his father's destabilising regional ambitions and oppressive domestic objectives," it said.
Khamenei's delegation of power to his son as well as of the authority to make decisions as he pleases is unconstitutional, say analysts.
The Islamic Republic is not a monarchy, and the leader is not to directly or indirectly appoint his family members to succeed him, said an Iranian legal analyst who specialises in the constitution.
"Yet Ali Khamenei has blatantly handed the reins over to his son, in total disregard of the constitution," he told Al-Mashareq on condition of anonymity.
"Sources close to senior regime officials say Mojtaba Khamenei is vying for his father's position. In doing so, many say he is attempting to circumvent [Iranian president Ebrahim] Raisi, although Raisi himself is a hardliner and an insider who is close to the leader," he said.
Mojtaba is known to be similar to his father in many ways but crueler, the analyst said.