Mariah Carey's Motto: No Champagne Before 3 P.M.

11/26/2008 at 08:55 AM EST

Is Mariah Carey pregnant? No way, the singer insists on Wednesday's episode of Ellen.

But DeGeneres seemed determined to put her to the test.

"Let's just toast with Champagne," the sly talk show host suggested, reaching for a bottle and some flutes.

"It's just fattening," demurred Carey – who married Nick Cannon in May – adding, "This is peer pressure!"

When DeGeneres persisted, the two clinked glasses – but Carey only pretended to drink the wine.

"You're pregnant!" DeGeneres declared.

"No, no, no," Carey insisted. "We will let you know when we're going to have a family."

So why refuse the bubbly?

"It's too early for me," explained the Grammy-winner. "I only drink after 3 p.m."

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