Gladys Knight and Patti LaBelle Announced for Next Verzuz Battle

Walter McBride/Getty Images Gladys Knight, Patti LaBelle

It's the Empress of Soul versus the Godmother of Soul!

Gladys Knight and Patti LaBelle are set to square off against one another on the next episode of the Verzuz battle series, the show announced Tuesday.

Calling their upcoming showdown on Sunday at 5 pm PT/8 pm ET the "Master Class we've ALL been waiting for," the program's Twitter account insisted that viewers have "gotta get dressed up in ya Sunday's best for this classic affair" between the two singers who, along with Dionne Warwick, previously collaborated on the hit "Sisters in the Name of Love."

The webcast show, which pits some of the music industry's most iconic singers against one another in a live battle, has showcased face-offs that have included Brandy against Monica, Babyface against Teddy Riley and more talented pairings.

Speaking of Brandy and Monica's competition, Democratic vice-presidential candidate Kamala Harris made a surprise appearance during their matchup on August 31, encouraging those watching to vote in the upcoming election on Nov. 3.

"Hi! I just wanted to thank you ladies. You queens, you stars, you icons," said Harris, 55, when she appeared via video chat on a monitor between Brandy, 41, and Monica, 39, who sat in chairs on a stage.

"Oh my God!" said Brandy.

"It's so important," Harris said of voting. "You both have used your voice in such a powerful way, and an extension of our voices is our vote, and so I know that this is going to help Michelle Obama's When We All Vote. ... Thank you all. I love you — I'm just a huge fan of both of you."

And in terms of upcoming Verzuz episodes, last Thursday night, the rapper T.I. reignited his feud with 50 Cent by challenging him to a rap battle as part of the popular Instagram Live series.

RELATED: 50 Cent Says He's a 'Better Specimen of a Man' as T.I. Challenges Him to Verzuz Rap Battle

And while LaBelle, 76, and Knight, 76, are set to sing their own songs on Verzuz, LaBelle recently opened up about how a beloved cover sung by Whitney Houston was almost hers.

LaBelle appeared on an October episode of Watch What Happens Live with Andy Cohen, where she revealed on the After Show that Dolly Parton had initially offered the song "I Will Always Love You" to her before Houston sang it in 1992’s The Bodyguard.

"I said to Dolly, 'Oh yes, I want to do that song, honey!'" LaBelle recalled to Cohen, 52. "But before I could say real yes, it was in the movie and Whitney killed it."

Capital Concerts/Capital Concerts via Getty Images Patti LaBelle

RELATED: Kamala Harris Makes Surprise Appearance During Brandy and Monica's Verzuz to Encourage Voting

And while plenty of other artists have covered "I Will Always Love You," LaBelle said she hasn't out of respect for Whitney.

"That was my little girl. She was so phenomenal," LaBelle raved about Houston, adding that she plans to put the song in her show as a tribute to Houston "one day."