Britney Spears sparked concern after holding a lighter to her tongue while dancing to JLo's song Booty in a bizarre video – after declaring she's meditated to Shakira's Hips Don't Lie.
The Toxic songstress, 41, showed off her moves in her gym gear – wearing a cropped top with the word 'LOVE' written across it in the Instagram clip.
Britney's preview picture shows her clutching a lighter, with the flame just inches from the chart-topping hitmaker's face – to the tune of Jennifer Lopez's song.
The tune features rapper Iggy Azalea, an artist who has previously collaborated with Britney on their song Pretty Girls released in May 2015.
In the caption, she wrote: "Found my hands with some red gloves !!! I meditated to Hips Don't Lie by @shakira !!! I just said keep shaking your a** and I did for 3 hours !!!"
She admitted her post was "not really punctual" and that she would likely "take [it] down in two days." She added: "I think I just found the playground."
The video comes after reports Britney is feeling "very nervous" and is "panicking" over the release of her ex-husband Kevin Federline's tell-all book on fatherhood.
She is thought to be worried about any revelations Kevin, who she married in October 2004, might make in his memoir about their previous spats.
The former couple divorced less than three-years after their wedding in 2007 after welcoming two sons – Sean Preston and Jayden – together.
Now Kevin, 44, is set to reveal all about raising their kids and his rollercoaster life in a tell-all book, something Britney is seemingly not looking forward to.
"She’s panicking over what Kevin is going to produce about her," said an insider – who claims Britney has penned her own book to "get her side of the story out there".
Speaking of the former couple, the source said: "They’re on poor terms right now so she’s very nervous about giving him any ammo to come at her when she does release her own life story.
"[Her husband] Sam [Asghari] and others in her team think she should wait and see what he says first, but Britney’s eager to go on the front foot and seize the initiative."
Britney has reportedly put pen to paper in a book deal thought to be around £12.3million, but 'paper shortage' is thought to have delayed its release since July last year.
The insider told Closer magazine that she hopes to get her book released before Kevin to clear the air before any of his book's claims.
"She has a lot to figure out in terms of the final content," they told the outlet. "Ultimately, this is her story so she’s free to tell it how and when she wants.
"It’s possible that she’ll rush to a conclusion in the coming weeks with her ghostwriter, and then get it on the shelves before Kevin and Jamie do."
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