Pauline Hanson says a Queensland "brat" who refused to stand for the national anthem should be kicked out of school.
Kenmore South State School grade four student Harper Nielsen, aged nine, was given detention and threatened with suspension for not standing when Advance Australia Fair was played in assembly.
She said she believes the lyrics "we are young" marginalises Indigenous people.
"The reason why I don't sing it or stand is because Advance Australia Fair means advance White Australia," she told The Courier-Mail.
"When it says we are young it completely ignores the fact that indigenous culture was here for over 50,000 years before colonisation."
Harper has the support of her "proud" dad Mark.
"She's shown incredible bravery in wanting to stick to what she believes in and to make a stance for what she believes is right", he told ABC radio on Wednesday.
But the stance has angered Senator Hanson, who posted a video on Facebook calling for Harper to be kicked out of school.
"Here we have a kid whose been brainwashed and I tell you what, I'd give her a kick up the backside," the One Nation leader said.
"This kid is headed down the wrong path and I blame the parents for it, for encouraging this.
"No. Take her out of the school."
Senator Hanson said there was support for the anthem amongst the indigenous community as sporting stars regularly stood for the anthem.
"I'm angry about this. I'm proud of the Australian flag and the national anthem as everyone should be and so was Cathy Freeman," she said.
"We were all proud of her, her cultural background, the Aboriginality, and the whole fact that she carried the two flags.
"She stood at the podium with the national anthem being played. Have they told this kid that?
"If it's good enough for Cathy Freeman, Johnathon Thurston, and Warren Mundine to stand for the National anthem, it should be good enough for this nine-year-old brat."
Shadow education minister Jarrod Bleijie echoed Senator Hanson's words, saying on Twitter she deserved suspension if she continued her protest.
"Stop the silly protest and stand and sing proudly your National Anthem. Refusing to stand disrespects our country and our veterans. Suspension should follow if she continues to act like a brat," he tweeted.
Australian Associated Press