Tensions between the judges went public late last year, when leaked footage from North Carolina auditions showed Minaj and Carey in a heated disagreement over a contestant.
Carey has since said she was putting any hostility behind her, but Minaj expressed her belief last week that the 'We Belong Together' singer simply dislikes her.
Seacrest promoted American Idol this week on The Ellen DeGeneres Show, where he admitted that there has been "tension" between Carey and Minaj.
"I have no idea what it's going to be like when we go live, which is sort of the exciting part of that," the American Idol host declared.
He went on to assure DeGeneres that both Carey and Minaj are actually making an effort to be civil to one another on the Idol set.
"I think that they're both trying to make for a great show and find great talent on the show," Seacrest disclosed. "So there will be moments that I'm sure we cannot predict."
American Idol airs on Wednesdays and Thursdays at 8/7c on Fox in the US. The show is broadcast on Thursday and Fridays at 8pm on 5* in the UK.
Watch a clip from Ryan Seacrest's appearance on The Ellen DeGeneres Show below: