"I'm very happy for you," McGregor continued.
"You're a f***ing warrior. You've got passion, courage, everything it takes.
"It takes a lot of courage to get in against a man, you know, after the first fight.
"I'm honoured to share the Octagon, and we will do it again.
"Thank you so much."
Before Sunday's encounter, McGregor's coach warned the first-round stoppage during their previous encounter at UFC 178 in 2014 would motivate Poirier.
"Your coach is right," Poirier told McGregor. "I can't forget, but I can forgive myself, and I have."
Another video posted by ESPN showed a limping McGregor lightheartedly telling Poirier: "You broke my leg, you b*****d. Great going, brilliant."
Speaking to reporters, McGregor blamed Octagon rust for the devastating defeat, conceding it was a "tough one to swallow".
"The leg was dead. I just wasn't as comfortable as I needed to be. It's the inactivity," McGregor said.
"If you put in the time in here, you feel cosy in here, and that's it. I have to dust this one off and come back and that's what I'm going to do.
"You don't get away with being inactive in this business."
In a juicy post-fight wash up, UFC commentator Ariel Helwani speculated a trilogy fight between McGregor and Nate Diaz is the right fight next for The Notorious, who desperately needs to regain some credibility before attempting a title run.
Helwani also told ESPN that Poirier will get to fight for a vacant title if Russian powerhouse Khabib Nurmagomedov continues to stay out of the game.
— with Tyson Otto