The “Tell Me You Love Me” singer, 25, also hinted at the duet during the Dallas stop of her recent tour. “Christina’s my girl and big things are coming,” she told fans.
Last year, Lovato also told Billboard she worked with “one of my biggest idols” but said she couldn’t yet reveal who she had teamed up with. “I can’t wait for the world to hear it. It’s an incredible song,” she teased at the time.
Lovato posted a jubilant message to Twitter following the announcement on Tuesday. “Dreams really do come true guys. Just work hard, practice and never give up!!!!!” she wrote.
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After years of promising fans that new music was on the way, Aguilera, 37, finally came through last week by dropping the first single off of her first new album in six years.
Her tune, “Accelerate,” is a laid-back R&B track that mixes her powerhouse vocals with rap verses from Ty Dolla $ign and 2 Chainz. “C’mon babe, pick up the speed,” she sings in the suggestive song. “Stamina. Fill me up. That’s what I need.”
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In April, PEOPLE exclusively announced that Shawn Mendes, Camila Cabello and Dua Lipa were set to take the BBMA stage. And on Monday, it was announced that Janet Jackson will be the recipient of this year’s icon award after a total of 18 BBMA nominations and 10 wins from 1990 to 2001.
Kendrick Lamar, Ed Sheeran and Bruno Mars are leading the nominations with 15 nods apiece, followed by Post Malone with 13 nominations in 12 categories, and Imagine Dragons with 11 nods in 10 categories.
The Kelly Clarkson-hosted Billboard Music Awards will broadcast live from the MGM Grand Garden Arena in Las Vegas on Sunday, May 20 at 8 p.m. ET / 5 p.m. PT on NBC.