'Hold Me Closer' Producer Says It Was 'Awesome' to Watch Britney Spears 'Crush It' on Track

Watching Britney Spears do her thing in the studio while recording "Hold Me Closer" was a dream come true for producer Andrew Watt, who said working with the star was "just iconic and amazing."

In her first new song in six years — and the first since her 13-year conservatorship ended in November – Spears, 40, joined Elton John, 75, for a dance-pop reworking of his hits "Tiny Dancer" and "The One."

Watt, who produced the track, told Rolling Stone that he and his team considered Spears a "long shot" to join them, as she'd previously said she had no interest in recording new music. But after a call from John, she quickly agreed, as "Tiny Dancer" is one of her favorite songs.

When she arrived at Watt's Los Angeles studio to record her part, she came prepared with input of her own.

"She came up with her own ideas. She wanted to speed up the record a little bit, and we did that," he said. "She knew exactly what she wanted to do. She had spent tons of time with the record; she knew all the lyrics; it was like, her thing."

Michael Kovac/Getty Britney Spears and Elton John

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He continued: "And it was really awesome to witness and see her be so powerful and crush it. She sounds incredible on the record, and she was involved all the way up until the final mix."

Watt said the pop star even added some adlibbing of her own, and eventually her vocals were mixed with John's to create the track as it is today.

"She was so free and improv-ing over it. That's where all the adlibs came from; she was playing off of the drop and that melody. Those moments are so 'her' and so much of her personality," he said. "I love that they're signing together, that their voices worked so good together," he said. "Once she sang that chorus, I threw my headphones in the air. I was like, 'Oh my God. It's like Britney Spears' voice singing 'Tiny Dancer.' It's just iconic and amazing."

"Hold Me Closer" was released last week, and quickly climbed the charts, reaching No. 1 on iTunes upon its release.

Spears expressed her excitement over its success in a video on Twitter, in which she spoke in a British accent.

"Hello Sir Elton John we are like No. 1 in 40 countries," she said before yelling: "Holy s—! I'm in the tub right now and I'm about to go have the best day ever and I hope you're well."

The legendary piano man responded to Spears' video, saying she "made my day."

He also reacted to the song's success himself, tweeting alongside a clip of the song: "I'm thrilled with the response to #HoldMeCloser I wanted to do a fun, happy summer track so was ecstatic when @britneyspears agreed to be a part of it! She truly is an icon, one of the all-time great pop stars & I love her dearly. I hope you all love it!"

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"Hold Me Closer" combines the chorus of John's 1972 smash "Tiny Dancer" and verses of his 1992 hit single "The One" with a fresh production. The track comes after last year's release of "Cold Heart," which reworked "Rocket Man" with the help of Dua Lipa.

John told The Guardian that it was actually his husband David Furnish's idea to bring Spears on for a feature. Because she was on her honeymoon at the time with husband Sam Asghari, she recorded her part at Watt's studio in Los Angeles in under two hours.