Britney Spears apparently had some unfinished business before her wedding to Kevin Federline.

In a new interview, Federline, 47, claimed Spears, 43, tearfully called her ex-boyfriend Justin Timberlake the night before they walked down the aisle in 2004.

“We’re at the Fairmont in Santa Monica in one of the bungalows,” he told Entertainment Tonight on Tuesday, October 14. “And I’m like, ‘What’s wrong?’ I thought she was talking to her mom on the phone or something and maybe she was, like, having doubts. And she told me that she was on the phone with Justin.”

Kevin Federline and Britney Spears
Kevin Federline and Britney Spears Michael Caulfield/WireImage

Federline recalled being taken aback and wondering whether he had heard Spears correctly.

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“[I was like], ‘We don’t have to do this,'” he shared. “I didn’t care if we got married or not.”

Federline said Spears immediately assured him that she simply wanted closure and to say her “final piece” to Timberlake, 44, after the ‘NSync alum broke up with her in 2002 for admittedly cheating on him with their mutual choreographer Wade Robson.

“I was like, ‘Damn, on the night before our wedding, this is what you decide to do?'” Federline remembered. “So I kind of at the time took it with a grain of salt and took her explanation as, OK, maybe she is closing a chapter of her life.”

Britney Spears and Justin Timberlake
Britney Spears and Justin Timberlake Jeffrey Mayer/WireImage

When ET cohost Kevin Frazier called the moment a “hell of a red flag,” Federline agreed, “Man, you’re telling me.”

“I was super young,” he added. “I was so madly in love at that moment.”

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Even after they said “I do,” Federline said he could tell Spears was not fully “over” Timberlake, but he swears he understood that the “SexyBack” singer was the Princess of Pop’s first love.

“I couldn’t imagine what it was like to be her. I couldn’t imagine or feel what it was like to be Justin in those moments because they were super young, right? You’re talking teenagers that had to go through this globally,” he noted. “And I know that they really cared about each other back then.”

Kevin Federline's
Kevin Federline Listenin

In response to Federline’s press tour for his upcoming memoir, You Thought You Knew, Spears’ rep said in a statement to Us Weekly earlier on Tuesday, “Once again he and others are profiting off her, and sadly it comes after child support has ended with Kevin. All she cares about are her kids, Sean Preston and Jayden James, and their well-being during this sensationalism.”

Us has also reached out to Timberlake’s rep for comment.

Britney Spears’ Dating History: From Kevin Federline to Sam Asghari

Spears and Federline welcomed their two sons, Preston, 20, and Jayden, 19, before separating in 2006. They finalized their divorce in 2007.

Spears was most recently married to Sam Asghari from 2022 to 2024. Federline, for his part, wed Victoria Prince in 2013, and they share two daughters: Jordan, 14, and Peyton, 11. Timberlake, meanwhile, tied the knot with Jessica Biel in 2012, and they have two sons: Silas, 10, and Phineas, 5.

You Thought You Knew is available in bookstores next Tuesday, October 21.