Georges St-Pierre says he’s VERY flattered by Kamaru Usman’s call-out … but he’s just not ready to un-retire and get back in the Octagon.

“I think for me it’s better if I stay retired,” GSP tells 360aproko Sports … “It’s not worth it for me.”

Of course, GSP formally retired back in 2019 — saying he wanted to leave while still on top (his last fight was a ’17 victory over Michael Bisping).

But, 39-year-old GSP still trains like a maniac — and people close to him say he’s still in dangerous fighting shape.

In fact, UFC welterweight champ Kamaru Usman called him out earlier this month — saying he would love to bait GSP out of retirement for one last fight before he truly rides off into the sunset.

But, St-Pierre tells us he’s given it some serious thought … and he just isn’t feeling a comeback — at least not right now.

“Sometimes I’m watching the fights and I’m like, ‘Man I think I can beat these guys’ or after when I’m done training I feel like I’m very confident,” GSP says.

“But, after I go home at night and I’m thinking about all that crazy thoughts and I’m like ‘I’m gonna be 40 years old soon, do I really wanna go back and do a hardcore training camp of 2 months? Put myself in jail so to speak and get ready for hell? I’m like, no I don’t.”

“I’ve done it for a very long time and unfortunately there’s too many guys that retire too late and I do not want to be one of these guys.”

“I’m very fortunate, I’m healthy most importantly and I’m also wealthy. I came out at the right time, I made a lot of money and I think the problems are when I matured and calculated the pros and cons, it’s better that i stay retired.”

GSP had nothing but praise for Usman — saying the guy is one of the smartest fighters out there and has big things in his future … but he’s just not ready to throw down right now.

But, watch the whole clip … St-Pierre says he’s always willing to entertain an offer if the UFC calls him up.

So, Dana … ball’s in your court.