Britney Spears' ex-husband Kevin Federline exclusively told Us Weekly that he's pals with the singer's other famous ex Justin Timberlake Credit: Tom Vickers

K. Fed, can you say that again… one more time!? In an exclusive interview with Us Weekly, Kevin Federline, who was married to Britney Spears from 2004 to 2007, reveals that he's pals with the "Pretty Girls" singer's famous ex-boyfriend — Justin Timberlake.

Spears, 33, began dating the "Mirrors" singer, 34, in 1999, amidst Timberlake's 'N Sync fame, but crushed fans everywhere when they not-so-amicably split in 2002. Timberlake later slammed the star (his fellow former Mouseketeer!) in his hit "Cry Me a River," while Spears went on to marry Federline, with whom she shares sons Sean Preston, 9, and Jayden James, 8.

"In the beginning when [Britney and I] first got together, it was awkward and I felt bad — I felt like maybe I should have called [Justin] and talked to him," Federline, 37, tells Us, laughing. "But I didn’t have his number."

Federline may have hooked up with Spears after her romance with Timberlake (oh, those matching denim outfits!), but the multi-Grammy winning entertainer hasn't held a grudge. In fact, the guys still bro out on occasion.

"We’re cool. Me and J are. I actually just went to his last show in Vegas and hung out with him, got to see a lot of old friends," Federline tells Us of Jessica Biel's husband, whom he used to backup dance for. "I’m friends with all the security guys. [They're] great, they’re incredible. We’ve actually — guys that work with him have worked with us and still work with me, still to this day. You know everybody, you’re friends with everybody. And yeah, me and J are cool."

He continues: "My best friend is his choreographer so we have mutual friends, and I mean, we’ve gone out golfing, we’ve hung out. You get older, you grow up, and you realize that was just a time in your life. Sh-t happens."

But do they ever talk about Spears? Not a chance. "No, no," Federline says. "Yeah, it is what it is to us." 

Federline first crossed paths with Spears when he was dancing on tour with LFO in the early 2000s. He says he looked at her like a kid (he was 21, she was 16 at the time), but they later introduced themselves at Joseph's Night Club & Lounge in L.A.

"I went out to a club, we just hit it off. It was weird. It was one of those things where, it just happened," he recalled. "I was just dancing on the dance floor and we kind of just had this chemistry...We both got very involved and interested in each other. And it just kind of took off from there."

Federline and the "Toxic" singer have found love with other people since finalizing their divorce, and they appear to be on good terms. Federline and his wife of three years, Victoria Prince, are parents to daughters Jordan, 3, and Peyton, 14 months. (Prince owns the ticket site Ticketdual.com.) He also shares daughter Kori, 12, and son Kaleb, 10, with ex-girlfriend Shar Jackson. Spears, meanwhile, called off her engagement to fiancé Jason Trawick in January 2013, and is currently dating Charlie Ebersol.

Up next, Federline will be DJing in Arizona, Colorado, and Chicago this month. To follow his travels, check him out on social media via Twitter @kevinfederline and Instagram @atfederline4real. Don't expect him to dish about Spears anymore though. He tells Us that he will no longer be discussing his past in interviews.

For more on Federline's exclusive interview and his relationship with Spears, pick up the new issue of Us Weekly, on stands now.

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