One Nation leader Pauline Hanson withdrew her support for her colleague Senator Rod Culleton on Tuesday in an interview with 2GB Radio.
"He's not a team player," she said.
"We can't work with him, you can't reason with him and honestly I think a whole lot's gone to his head.
"He loves the limelight, he loves the publicity and he's not really listening to the advice you know."
She said she will pursue his push to establish a Royal Commission into banking, but ultimately "he runs his own race".
Her statements follow Rod Culleton's public criticism of Ms Hanson on Monday. He she had failed to back his attempt to leverage on the backbacker tax for a Royal Commission into banking last week.
The Greens Party obtained a further 100 million for Landcare Australia from the government in return for its support of the changed backpacker tax of 15 per cent.
Mr Culleton will face a High Court hearing on Wednesday over his eligibility to have run for parliament.
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