In a series of X posts on Sunday, Khamenei said the "enemy of Islam" seeks to exploit racial, cultural, social, economic, political and geographical differences to sow division among Muslims.
Adding to the speculation surrounding his status, President Masoud Pezeshkian acknowledged in a state TV interview that direct interaction with Khamenei is currently "very difficult."
Mojtaba has not appeared in public since his appointment in early March. The late supreme leader's other three sons, Masoud, Mostafa and Meysam, all attended the service.
