DUP MLA Jim Wells said the reason he has gone public on his disagreement with former party leader Peter Robinson is that he believes the party is moving to replace him.
Mr Wells sparked a public row with Mr Robinson last week, claiming that the former first minister assured him he would be reinstated as a minister before his high-profile resignation in 2015.
But the public exchange had prompted some to ask why Mr Wells had chosen to go public now – three years after his resignation – which came after remarks he made about homosexuality made international headlines.
“The reason I have chosen to go public now is entirely due to the fact that the party is working within the constituency to replace me,” Mr Wells said.
“And this despite the fact that I am the only unionist MLA in South Down, where I have been a member of the Assembly for 24 years.”
The party now has a South Down DUP Facebook site which appears to be led with images of all DUP South Down representatives except for Mr Wells.
The MLA said he has excellent support from the DUP in South Down.
“But if the association nominated me for the next election it would have to approved by the party centrally.”
It was more likely that the association would be forced to accept the central party’s candidate, he said.
“But I am not stepping down as MLA. I will not leave the DUP, I still support the party policies.
“All I want is to be vindicated by the party and then I will retire.”
He would not consider joining another party but has not ruled out standing again as an independent.
In April 2015 a video clip was published on social media which critics believe showed him linking homosexuality to child abuse. Mr Wells resigned as minister within days but in October 2015 the Public Prosecution Service decided not to prosecute for hate crime, saying it had reviewed a fuller transcript.
Yesterday the News Letter published an email from Mr Robinson which Mr Wells believes constituted a promise to reinstate him as minister.
However, Mr Robinson has told the BBC’s Stephen Nolan that he had not made any such promise to Mr Wells and had been “much more careful” with his words.
The DUP declined to respond to claims that it was working to replace the South Down MLA.
“The party is aware of the comments,” it said. “This is an internal matter. The party will not be giving a running commentary.”