"I think words and actions are important," he said. "I think it's impractical [to work with LIV Golf] when you look at the fact that certain players have sued the PGA Tour, their employer has sued the PGA Tour.
"It's not in the cards. It hasn't been in the cards and it's not in the cards. I think we've been pretty consistent on that front."
Given the current feud in the golf world, and the lawsuit that Monahan mentioned, his stance shouldn’t be surprising.
Mickelson has been the face of the controversial Saudi Arabian-backed golf venture, and has received by far the most criticism for his participation in it. He was also part of the lawsuit against the Tour, though he and several others officially asked to be removed from that on Tuesday.
"LIV Golf is here to stay. The best solution is for us to come together," Mickelson . "I think that the world of professional golf has a need for the old historical 'history of the game' product that the PGA Tour provides … I think both are needed for the game of golf. Both are good for the game of golf. The inclusion of LIV Golf in the ecosystem of the golf world is necessary."
Monahan, however, sees things very differently. The two leagues coexisting, he said, doesn’t make sense.
"The answer to that is they've gone down their path and I think we have been pretty consistent that we're going down ours, and I don't see that happening," Monahan said. "Haven't, and I don't."
In the end, Monahan believes only the PGA Tour will survive.
"The game, at the highest level, is about aspiration. It's about context," he said. "And any young kid today, any kid that's going to be playing the game going forward, ultimately is going to want to win the biggest championships, the biggest tournaments, and put themselves in a position and on a path over the course of their golf journey to get to the PGA Tour and to again, achieve at the highest level. We are going to continue to evolve and get stronger in every single area of that spectrum or of that journey."