Insisting that the teens love their mother, Federline told the publication, "The boys have decided they are not seeing her right now. It's been a few months since they've seen her. They made the decision not to go to her wedding."
Federline also said he has had a hard time explaining Spears' decision to post nearly nude photos online to his two sons. "'Look, maybe that's just another way she tries to express herself,' " Federline explained as to what he has said to his sons, he told The Daily Mail. "But that doesn't take away from the fact of what it does to them. It's tough. I can't imagine how it feels to be a teenager having to go to high school."
Kevin Winter/Getty; Kcr/Shutterstock
Spears reacted to Federline's statements in an Instagram Story post on Saturday evening, where she wrote, "It saddens me to hear that my ex-husband has decided to discuss the relationship between me and my children."
"As we all know, raising teenage boys is never easy for anyone. It concerns me the reason is based on my Instagram. It was LONG before Instagram," she continued, referencing Federline's issue with her social media posts.
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Noting that she "gave them everything," the "Me Against the Music" singer added, "Only one word: HURTFUL."
"I'll say it... My mother told me 'you should GIVE them to their dad' ... I'm sharing this because I can … Have a good day folks!!!" Spears concluded.
The mother of two later spoke out against Federline once more in a post shared on her Instagram feed.
"Reminder that the trauma and insults that come with fame and this business not only affect me but my children as well!!!!!," she wrote in part. "I'm only human and I've done my best...I honestly would like to share my TWO CENTS!!!! I daringly would like for the Federline's to watch the BIG BOOTY VIDEO !!! Other artists have made much worse when their children were extremely young!!!"
Asghari, 28, also chimed in to express support for Spears. In an Instagram Story post of his own, he spoke out about Spears' social media posts and how the images and videos she shares online are more "modest" than those shared within advertisements and by others.
"There is no validity to his statement regarding the kids distancing themselves and it is irresponsible to make that statement publicly," Asghari continued. "The boys are very smart and will be 18 soon to make their own decisions and may eventually realize the 'tough' part was having a father who hasn't worked much in over 15 years as a role model."
Asghari then noted that while he doesn't know Federline personally, he has "nothing against him aside from him choosing to vilify my wife."
"His character is revealed by approval of the cruel 13 year CShip and his loyalty to [Jamie Spears] indicates his approval at the time of its conception as well," Asghari said, referring to the years-long conservatorship that Spears was put under by her father. "Things that are now considered normal issues and behavior easily dealt with therapy or other ways were magnified to justify a 13 year prison sentence. Anyone approving of it is wrong or benefiting from it somehow."
He concluded his statement by noting that he had no further comment, but in a second Instagram Story post, Asghari wrote, "I wish him the best and hope he has a more positive outlook in the future for benefit of all involved."
"But for now: Keep my wife's name.....out your mouth," he added.
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"Britney walked herself down the aisle. She looked absolutely stunning in her main dress," an insider previously told PEOPLE. "She cried happy tears at some moments."
Ahead of Spears' special day, Mark Vincent Kaplan, Kevin Federline's longtime attorney, confirmed to PEOPLE that Sean and Jayden wouldn't be in attendance when their mom said "I do."
"They're happy for their mom and they are hopeful that Sam and Britney are starting a great future together," he said at the time.
Kaplan added: "It's their night and they didn't want to take away from them."