EXCLUSIVE: Andy Cohen Reveals 'Real Housewives: All Stars' Will Happen Eventually

The 'Watch What Happens Live' host tells ET he's thought a lot about the idea.

“Go to sleep! Go to sleep!”

Bethenny Frankel shouted those infamous words at Kelly Bensimon on The Real Housewives of New York back in 2010 on a vacation known to fans as “Scary Island.”

Now, picture Bethenny doing that to a Housewives star from another city, say Beverly Hills’ Brandi Glanville or New Jersey’s Danielle Staub. Well, king of the Housewives, Andy Cohen, tells ET executive producer Brad Bessey it could happen.

“You know what? We will do Real Housewives: All Stars when the show is just about out of gas,” Cohen reveals. “So right now we had our second highest season of Beverly Hills, New York’s highest ratings since 2012, and Orange County, last season had it's highest rated season in 10 seasons.”

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“So, we are nowhere near the point where we need to put eight of them on an island,” Cohen jokes, adding that a Below Deck-style boat adventure is a possibility, too.

“We will, and I can't wait to do it,” Cohen adds. “But it's going to be at the end of the line … We'll do it at the end. It's something that we don't waste now. We want to save it for later.”

In the meantime, some familiar faces from Real Housewives history could make their way back to TV. The franchise is a mafia of sorts.

“I'm their boss and their cheerleader,” Cohen says of the cast members. “And sometimes, their stern dad. You know, boss, stern father, and always cheerleader. Because I want them to do well and I want them to do well on the show. It only benefits me if they're on the show for a really long time, and people love them.”

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Cohen says NeNe Leakes may be back full-time next season on Real Housewives of Atlanta. At very the least, she’ll “dip her toes in.”

The Watch What Happens Live host also confesses he’s interested in seeing Jill Zarin back on Real Housewives of New York. Longtime star Luann de Lesseps recently opened up to ET about that idea. See what she had to say in the video below.