Hashem Safieddine, a cousin of Nasrallah and a designated terrorist by the US State Department since 2017, emerged as his successor.
As head of Hezbollah's executive council, Safieddine oversees the group’s political affairs and is a member of the Jihad Council, which manages military operations.
But media reports citing a Lebanese security official on Saturday have indicated that the new leader has as been out of contact since Friday after a targeted strike by Israel.
In addition to uncertainty over Safieddine’s presence, deputy leader since 1991 Naim Qassem has reportedly resigned from his position.
During a recorded speech following Nasrallah's death last week, Qassem appeared visibly distressed and uncomfortable, leading to speculation about his future involvement with the group.
His resignation would mark a significant shift in Hezbollah's hierarchy as Qassem has been a stalwart of the organisation for decades.
With Israeli ground forces crossing into southern Lebanon last week, the situation remains extremely volatile.