The singers made a cryptic announcement Thursday on social media ... posting images of each other in very similar outfits -- but without revealing their faces. They captioned their posts, "Get ready" and "This is happening."

Pepsi then posted the big reveal image showing both women's faces. BTW ... makes sense the NFL would draft co-headliners for the Miami event, because deuces are wild -- the Super Bowl date is 02/02/20.

When the NFL announced its new partnership with Jay-Z, it said his company, Roc Nation, would be helping secure talent for the Super Bowl Halftime Shows. We're told Roc Nation was heavily involved in closing this deal -- and we also hear ... there will be a few more surprise acts joining J Lo and Shakira.

Shakira last released music in 2017 -- the album, "El Dorado" -- and in November she's releasing a feature film worldwide which documents the El Dorado tour. Jennifer just wrapped her own 2019 "It's My Party Tour."

There's been a buzz in recent weeks about J Lo scoring the gig. In fact, she openly said, "It's something that we've talked about for many years, and, y'know, it would be nice. I can't say I wouldn't love it."

Wish granted J Lo ... see ya in Miami.