"Just calling for an immediate cease-fire to really ensure the safety for innocent people. We really want to stop killing kids and make sure everyone's safe," Youssef said.
Youssef, who played Max McCandles in the Yorgos Lanthimos' film, is wearing a pin in solidarity for the Artists4Ceasefire cause.
"It's really just a humanitarian issue that a lot of artists are passionate about."
Billie Eilish and brother Finneas also were seen wearing the Artists4Ceasefire pin.
Nearby the Oscars at the Cinerama Dome, demonstrators have lined the streets to protest and call for a cease-fire in Los Angeles.
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