Addressing a media briefing in Lahore alongside Punjab Minister for Prisons Fayyazul Hassan Chohan, after a sessions court granted him bail, Nazir said that he no longer has "any association with the Tareen group".
"Jahangir Tareen used me for his case and then threw me away," he said.
Nazir said that he was "never once called" by Tareen in his hour of need, whereas he went to every court summon of Tareen.
"I considered him my leader, but he is not fit to be called one," Nazir said of Tareen.
Nazir expressed his gratitude to the senior PTI leadership, naming Chaudhry Pervaiz Elahi and Shahzad Akbar in particular.
"I am grateful to Chaudhry Pervez Elahi who took a strong stance for me," he said, adding: "Shahzad Akbar was the first to call me when I fell ill and inquired about my health."
"I have apologised to Shahzad Akbar in no unclear terms. I am remorseful over my actions which affected him and his family," he said.
Nazir went on to state that he has "one leader and one leader alone," adding: "His name is Imran Khan."
He said that Tareen "should be ashamed of himself for not even bothering to visit" him in the hospital.
The PTI member said that in this entire saga, "the faces of a lot of hypocrites have been exposed".
Fayyazul Hasan Chohan, for his part, acknowledged that conflict within the party had been brewing for a while but that the disgruntled party members took the senior party leadership into confidence over their concerns.
"Shahzad Akbar played a positive role in assisting mediation efforts," he said, adding: "Nazir Chohan also played a vital role in this regard."
"We have no right to object to anyone's faith and probe such matters," he added.