Britney Spears’ high-powered attorney, Mathew Rosengart, is slamming a “false and defamatory” report linking the “Toxic” singer to crystal meth use.

Rosengart sent the Daily Mail a legal letter Sunday — which was reviewed by Page Six — in which he calls for an internal investigation concerning the exploitation of Spears’ minor children, Sean Preston, 17, and Jayden, 16.

“The Daily Mail, through Daphne Barak, posted a story yesterday containing numerous false and defamatory fabrications concerning my client Britney Spears that are attributed to Kevin Federline and his children, in particular regarding ‘crystal meth,’” the letter began.

He noted that Federline, who was married to Spears from 2004 to 2007, “acknowledged the falsity of Ms. Barak’s story” when he spoke to TMZ earlier today.

Rosengart went on, “I have separately learnt that on several occasions, Ms. Barak sought to contact Britney under false pretenses, again her minor children, which is exploitative, harassing, and outrageous.”

“And moreover, Britney’s representatives were never contacted prior to the publication of the story, further demonstrating actual malice and reckless disregard for the truth.”

The letter concluded, “Britney is indeed a public figure, but this conduct is beyond the pale and completely unacceptable. It is shoddy even by today’s standards of ‘journalism’ and the unfair scrutiny she has faced.

“I will follow up separately, but for present purposes, please confirm that the Daily Mail will immediately delete and retract that false and defamatory story and conduct an internal investigation regarding this matter and the abuse of Britney and her children.”

At the time of publishing, the story was still live on the Daily Mail website.

When contacted for comment, Barak told Page Six, in part, “There are 12 days filming with Federline, his wife, his family and others. All – By his request.”

She noted that only a “small percentage” of the footage she documented “has been released and made headlines.”

Earlier today, Federline called out Barak for “fabricating” his quotes, alleging to TMZ that she “lied” in a “distressing” report published by both The Sun and Daily Mail.

“It saddens our family that Daphne Barak and Erbil Gunasti have decided to fabricate lies and publish the heart ache our family has endured, along with the trauma of our minor children in the Daily Mail and The Sun,” Federline, 45, told the outlet, referencing Gunasti, who has worked on several projects with Barak.