A furious backlash against federal MP Bob Katter is set to deprive him of key Labor preferences and union money after he fully endorsed his senator Fraser Anning's notorious "final solution" speech.

But while one union donor confirmed it would no longer support Katter's Australian Party, the giant Construction, Forestry, Maritime, Mining and Energy Union refused to say whether it would disown Mr Katter.

The far north Queensland MP has been shunned by acquaintances in the wake of his furious support for Senator Anning, who used his debut speech to call for a ban on Muslim migrants and praise the discriminatory White Australia Policy.

Liberal National MP Warren Entsch, whose seat borders Mr Katter's, said his political neighbour was too often dismissed as "just being a little bit wacky [or] a little bit eccentric".

"They always refer to him as a maverick. He’s not a maverick," Mr Entsch told Fairfax Media.

"Instead of putting him up there on a pedestal as the anti-politician, he should be called out for what he is. Quite frankly, I think he's almost certifiable."

Mr Entsch called on Labor and the CFMMEU to stop backing Mr Katter, who was narrowly re-elected on Labor preferences in 2013 and received Labor preferences again in 2016.

"He only stays in the Parliament because of support of the Labor Party," Mr Entsch said. "We should all be putting them [KAP] last."

Labor's chief tactician Tony Burke, who spoke passionately against Senator Anning's ideas this week, told Fairfax Media his party would reconsider giving its preferences to Mr Katter.

"We've always put One Nation last ... because of the racist element of that party," Mr Burke said.

"All the reasons that lead us to put One Nation last need to be applied to any party playing the same racist, divisive games.

"It's not for me to announce today, but I think it's pretty clear where we're headed."

In comments that will make it harder for Labor to back KAP in any form, long-serving Labor senator Kim Carr said Senator Anning had displayed "attitudes which can only be described as fascist since the very day of his arrival".

However, others in Labor were more circumspect. NSW senator Doug Cameron said that given he is a left-wing unionist, "Bob Katter doesn't represent my views", but donations were "a matter for the CFMMEU". Queensland's Murray Watt, a vocal critic of One Nation, did not respond to a request for comment.

Since 2011-12, the CFMMEU has donated $200,000 to KAP. Neither its national or Brisbane offices - nor its national secretary Michael O'Connor - responded to Fairfax Media's questions on Thursday.

But support from other elements of the union movement has evaporated. The Victorian branch of the Electrical Trades Union previously gave $100,000 to Mr Katter's party, but secretary Troy Gray told The Guardian he would be "staggered if anyone in the union movement" backed KAP again.

Others also distanced themselves from Mr Katter. Centre Alliance MP Rebekha Sharkie welcomed Mr Katter's support during her recent byelection campaign in the seat of Mayo, but told the ABC she would not accept his help again.

Greens senator Peter Whish-Wilson, who worked with Mr Katter on the banking royal commission, said he "expected better" of the Queenslander. "His legacy will now be trying to outdo One Nation on racial hatred," he said.

Other MPs highlighted Mr Katter's poor record of attending Parliament and participating in votes. In his previous term he missed 80 per cent of divisions. Mr Katter was absent from Canberra again this week - he said this was due to a medical operation meaning he could not fly.

Mr Katter, 73, told Fairfax Media he planned to recontest his seat of Kennedy, which he has held for 25 years, but reserved the right to change his mind. He said no one from the CFMMEU had contacted him about Senator Anning's speech or his subsequent statements.

"I can’t think of any reason why they would," he said. "We are being undercut by massive migration into Australia [and] the only people fighting against that are ourselves [KAP] and the CFMMEU."

Mr Katter also dismissed criticism from Mr Entsch. "He would be a person that would know how dangerous I am because he’s set to lose his seat in the forthcoming election," he said.