DUP leader Sir Jeffrey Donaldson said he did not encourage his colleague Edwin Poots to switch constituencies to stand in South Down just days before party officers rejected his nomination.
Sir Jeffrey insisted it is not his job to determine which candidate will stand in which constituency for the Assembly elections.
Last Friday night, DUP party officers selected Diane Forsythe as the candidate for South Down ahead of Mr Poots, Stormont's current agriculture minister, who was attempting to switch to the constituency from Lagan Valley.
The decision has to be ratified at a meeting of the party's executive next week.
Earlier this week, Mr Poots, a current Lagan Valley MLA, said he agreed to take the political risk of switching constituencies to ensure Sir Jeffrey would have a "seamless" route back to Stormont from Westminster.
He said he was "encouraged to stand in South Down up until the middle of last week by the party leader".
But Sir Jeffrey told the BBC Good Morning Ulster programme it is not his place to interfere in the selection process.
He said: "Of course Edwin and I have talked about the situation in Lagan Valley, because we are looking to contest the election there and we have strong candidates.
"Edwin, after Jim Wells was not going forward for South Down, indicated to me that he was prepared to put his name forward for South Down.
"It is not my place to interfere in the selection process. It is not my place as party leader to determine who should be a candidate in any constituency.
"There is a proper selection process to be gone through. We have rules in place. Those rules have been abided by."
He added: "I am very clear, I did not encourage or discourage anyone to do anything.
"It is not my role as party leader to decide who should stand where.
"Edwin made clear that he wanted to go forward for South Down. I said that he should put his name to the party officers and his name would be considered.
"I believe Edwin has an important role to play on our team. He is doing a good job as our minister for agriculture
"I want to see Edwin continuing to be part of our team.
"It is a matter for each individual candidate to decide what they do.
"Edwin has chosen to go for South Down, that is his right to do so. I would not stand in his way if he wants to do that."
Earlier this week, Mr Poots said he "hasn't gone away" after failing to secure the South Down nomination, and indicated that the selection process is "incomplete" because it has not been ratified yet.
Jim Wells, the current South Down MLA, previously indicated he believes the decision of the party officers can be overturned and that Mr Poots could still be the candidate in the constituency.
