Britney Spears releases song fans outside of Japan might have never heard before

Britney Spears just released her song "Mood Ring," worldwide on Friday.

The song -- which, up until now, was only available in Japan as part of her 2016 album "Glory" -- has been made available on streaming platforms for all fans to enjoy.

The 38-year-old pop singer first announced her plans to release the sultry track, produced by DJ Mustard, in an Instagram Story on Thursday night.

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"You’ve been asking for it," she revealed. "Mood ring. Tonight."

The new-ish song comes weeks after fans drove Spears' "Glory" album to the No. 1 spot on the iTunes charts with the #JusticeForGlory campaign and, to celebrate, she revealed a brand-new cover for the album.

Alongside the new album artwork, which features the pop icon in a tiny gold bikini as she arches her back on the ground in a desert, she wrote, "You asked for a new Glory cover and since it went to number one we had to make it happen !!!! Couldn’t have done it without you all."