TUV leader Jim Allister has distanced himself from a party member at an anti-Protocol rally who labelled Ulster Unionist leader Doug Beattie a "Lundy".
Roy Ferguson, a former TUV Assembly election candidate, also branded Mr Beattie a "traitor" as he addressed the protest in Lurgan against post-Brexit trade arrangements.
The demonstration last Friday in Co Armagh has faced criticism after a poster of Mr Beattie was displayed with a noose around his neck.
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Mr Allister and DUP leader Sir Jeffrey Donaldson removed the poster and condemned the display, which came after Mr Beattie withdrew from the rallies over claims they are being used to raise tensions.
Mr Ferguson stood for TUV in Upper Bann in the Assembly elections in 2016 and 2017.
He also signed the nomination papers of the party's candidate for the constituency in May's election, Darrin Foster.
Asked about Mr Ferguson's remarks at the rally about the UUP leader, Mr Allister said he "gave no support or applause to those comments".
He told the BBC's Nolan Show : "I think that was wholly wrong. 'Lundy' has a particular pernicious meaning in loyalist circles and there was nothing to justify calling Doug Beattie a Lundy or a traitor."
Mr Allister also hit out at the "mindless idiots" who displayed a "ridiculous" poster of Mr Beattie with a noose around his neck.
He said it has "distracted from the very clear message and the very great success of that rally".
The TUV leader also said he did not know he would be sharing the stage with a contentious US pastor who has since faced criticism for previous remarks.
Mr Allister said: "I didn't know anything about this gentleman until he appeared on the stage."
Mr Ferguson did not respond to requests from Belfast Live for a comment.
A series of rallies have been taking place across Northern Ireland outlining unionist and loyalist opposition to the Northern Ireland Protocol, which sees additional checks on goods arriving into Northern Ireland from Great Britain.
It is strongly opposed by unionists who regard it as creating a border in the Irish Sea with the rest of the UK.
There is no suggestion the organisers of Friday's protest are connected to the Mr Beattie poster.
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