The viral video was initially posted to YouTube and Facebook last week by the Islamic Education Center of Houston (IEC), which organized the event calling on parents to bring children aged 4-14, according to its social media pages.

"Seyed Ali is calling on his children, his soldiers, who were born in the 2010s," the children sang in Houston, using Khamenei's first name (Ali) and honorific title (Seyed). "In spite of my age, I will be your army's commander … Don't look at my young age. May my father and mother be sacrificed for you. I will sacrifice everything for you."

Wearing headbands, waving flags, and saluting, the children sang: "I make an oath, one day when you need me. I make an oath, to be your martyr."

Observers have argued the song, which has been heavily promoted by Iranian state media, is part of the regime's efforts to secure support among the youth. Schoolchildren in Iran are reportedly being forced to sing and memorize it in school.

Activists have lambasted the song as regime propaganda that seeks to recruit child soldiers and brainwash children, drawing comparisons to the Hitler Youth in Nazi Germany.