Naim Qassem was chosen as the new leader of Hezbollah on Tuesday morning.
Qassem is a veteran figure in the group, having served as deputy secretary-general for the Lebanon-based terrorist organization for over three decades. He relocated to Tehran earlier this month due to fears that Israel would assassinate him.
Israel had previously eliminated the former leader, Hassan Nasrallah, and Hashem Safieddine, who was rumored to take Nasrallah's place before his own assassination.
An Iranian source told the Emirati website Aram News that Qassem left Beirut on an Iranian plane, accompanied by Iranian Foreign Minister Abbas Araghchi, for Damascus, and from there, he continued to the Iranian capital.
Qassem first entering politics
His political activity began in the Lebanese Shi'ite Amal Movement, which he left in 1979 after Iran's Islamic Revolution. He took part in meetings that led to the formation of Hezbollah, which was established by Iran's Revolutionary Guards in 1982.
Qassem had also been considered the de facto leader of the terror group since Nasrallah's assassination. Before his promotion, he was one of the leading spokesmen for Hezbollah, conducting many interviews with foreign media.
As cross-border hostilities raged with Israel during the Gaza war, he told Al Jazeera in June that Hezbollah's decision was not to widen the war but that it would fight one if it were imposed on it.
He then claimed in a televised address at the beginning of the month that Hezbollah is "steadfast, and we will emerge victorious," while claiming that the terrorist organization's capabilities were intact.
Reuters contributed to this report.