The UFC superstar was speaking with reporters in his native Dagestan Tuesday when he was asked about the comments his manager, Ali Abdelaziz, made to TMZ Sports about moguls in Saudi Arabia offering $100 mil to host the rematch.

That's when Khabib scoffed at the possibility -- saying he's only focused on fighting Tony Ferguson in April -- but says that kind of money could be better used by helping the needy.

"Why do I need that kind of money?" Khabib said ... "There are so many organizations. For example, there’s not only [soccer] for the blind, there’s sambo and other sports."

"Let [the UFC] give it to them if they don’t know what to do with the money. But giving me $100 million for me to beat up that idiot again? I don’t think that’s rational."

When asked if there was interest in a rematch with Conor -- as McGregor has called for numerous times -- Khabib replied, "Not at all."

The comment was met with cheers from the Dagestani crowd.

As for his April 18 fight with Ferguson, Khabib called it a "very serious fight" ... and he's been training like a maniac.

"For the past month and a half, I’ve been consistently training day and night. I’ve gotten myself in good shape to where I’m supposed to be 70 days before a fight. I feel great."

Guessing McGregor will respond.

Stay tuned ...