"I declare that these protests and instability were planned by the United States and the Israeli regime, their cohorts and some treacherous Iranians abroad helped them in this matter," Khamenei was quoted as saying by Iranian news agency Tasnim.
Last week, Iranian authorities declared that the protests have come to an end.
Amini was detained by the police in Tehran for wearing an "improper" hijab, an offense punishable by prison, on September 13. She was sent to one of the centers belonging to the police department and military intelligence for an explanatory conversation, where she had a heart attack and passed away on September 16.