"Conor is a competitor, man. He loves to fight. This is his passion in life," White tells TMZ Sports.

So, who's the opponent?? That's the tricky part.

Dana says he wants to see how the fights at UFC 238 this weekend shake out before announcing an opponent for Conor.

Remember, one of the most important fights of the weekend is Tony Ferguson vs. Donald "Cowboy" Cerrone ... both of whom want a crack at McGregor.

Dana tells us he knows Conor's goal is to get his rematch with Khabib Nurmagomedov ... but Khabib's already committed to fighting Dustin Poirier in September.

"We gotta see how everything plays out," Dana says.

The one thing White would ABSOLUTELY commit to -- Conor will fight in the Octagon before the end of the year.

It's a big deal considering back in March, Conor had said he was retiring from MMA to focus on his whiskey business.

He later said he WOULD fight again if Dana offered him an ownership stake in the UFC -- something Dana has said he simply WILL NOT do.