Pauline Hanson's One Nation is two nations now.
The three-person Senate team is split over supporting the government's company tax cut plans, with Senator Brian Burston deciding to back them.
She's been accused of making decisions without consulting her party, and leaving long-time supporter Senator Burston in the lurch.
Senator Hanson insisted the party was united, before walking out of a press conference while colleague Peter Georgiou was still talking.
"Is it hard to show you're united when your boss just walked away?" one journalist asked him.
"Actually I didn't realise she'd walked away so I'll be walking away now too, thank-you very much," Senator Georgiou replied.
Senator Burston has taken the One Nation branding off his social media accounts, and it's understood he told staff to advise him only, rather than the party team.
The government was told about a month ago of his solid support for corporate tax cuts, irrespective of any possible future change of heart by Senator Hanson.
The One Nation leader reneged on the handshake deal she struck with Finance Minister Mathias Cormann, so Senator Burston decided to go public.
He is understood not to favour quitting One Nation in the short term, but will be voting contrary to his party colleagues from time to time.
"He's said he's not doing a dummy spit, he said he's not walking away from One Nation," Senator Hanson told reporters.
But David Leyonhjelm, who had dinner with Senator Burston last week, said Senator Hanson - who recently declared herself the party president-for-life - was making all of the party's decisions often without consulting colleagues.
Senator Leyonhjelm said she had "anointed" former senator Malcolm Roberts as the lead candidate for the party in Queensland, but so far declined to do the same for sitting senators Burston and Georgiou.
"She made it plain to them and said 'I'm looking around to see if there is anyone better' - it's not a formula for love and affection," Senator Leyonhjelm said.
"In Brian's case he's been a loyal supporter of her for 20 years. He is fairly hard done by."
Senator Hanson said preselection wasn't finalised, but pointed out to her long-time supporter that just because he's a senator doesn't mean he'll automatically be endorsed.