Senator Fraser Anning has been expelled from the Katter's Australian Party (KAP) due to his views on immigration and race.
The Queensland senator's time in Federal Parliament has been tumultuous, with him leaving One Nation just hours before being sworn in to the Upper House after a spat with leader Pauline Hanson.
He joined KAP after a short stint as an independent and was criticised for using the term "final solution" during his first speech on migration.
At the time, KAP leader Bob Katter strongly supported Senator Anning's speech, describing it as "solid gold".
But on Thursday, Mr Katter said the party's executive decided only "99 per cent" of it was solid gold, and that the rest was "totally unacceptable".
Mr Katter said he had repeatedly warned Senator Anning not to use racially charged language or call for a European immigration program.
"Clearly that is racist," Mr Katter said.
"This position was made perfectly clear again following a bill that Senator Anning had drafted."
Senator Anning last week sought to introduce a bill for a plebiscite on non-European migration to Australia, "to give the people a say on who comes to this country".
"We've had a plebiscite on same-sex marriage. This is a far more important issue, and it's one the Australian people, I'm sure, would like to have a say in," Senator Anning told reporters last week.
Senator Anning said his plebiscite would also ask whether "Muslim immigration" should be stopped.
He denied this was bigoted, saying it was not "bigoted at all to give Australians a say in who comes here".
Mr Katter on Thursday said he would have voted against the bill if it ever came to Parliament.
"He was unequivocally informed that when the party learned of this bill that there would be extreme hostility if the bill went forward using racial identification terminology," Mr Katter said.
"We have championed the cause of the Sikhs, I've moved legislation in here on behalf of the Sikhs, we've championed the cause of legislation for the Jewish people.
"We've championed the cause, and I will often speak as a First Australian, I identify very strongly as a First Australian."
