Jada, 48, was good friends with the late rapper, who was murdered during a drive-by shooting in Las Vegas back in 1996. The pair attended the same performing arts school in Baltimore.
When Smith, 51, appeared on US radio show The Breakfast Club to promote upcoming film Bad Boys For Life with co-star Martin Lawrence, he was asked whether he ever felt jealous of the love Jada had for Tupac.
Responding very honestly, Smith said: "Oh f*** yeah. Oh my God, that dude. You know, that was in the early days. That was in the early days and it was like, that was a big regret for me too 'cause I could never, I could never, open up to interact with Pac.
"We had a little bit of a thing, right, because you know they grew up together and they loved each other but they never had a sexual relationship. But they had come into that age where now that was a possibility and then Jada was with me."
He went on: "Pac had a little thing on that but she just loved him. He was the image of perfection but she was with the Fresh Prince.
"It was like... even [though] we were in the room together a couple of times, I couldn't speak to him, you know, and he wasn't going to speak to me if I wasn't going to speak to him."
One of the hosts, Charlamagne Tha God, was surprised by this revelation, saying: "Really? I thought you would have so much in common."
Smith replied: "That's what Jada would say all the time.
"She was like, 'I'm telling you, y'all are so similar, you will love him,' and I just never... that was a huge regret of mine.
"I just didn't, I couldn't handle it. I was the soft rapper from Philly and he was Pac. I was deeply, deeply insecure and I wasn't man enough to handle that relationship."
Speaking about Tupac's death in 2018, Jada said: "He was one of those people I expected to be here. My upset is more anger because I feel like he left me.
"And I know that's not true and it's a very selfish way to think about it... I really did believe he'd be here for the long run. And when I think about it I still get really mad. He played his role...he did what he was meant to do...he's an icon."
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