The judges were speaking at the Television Critics Association Winter Tour when things between Nicki and Mariah turned sour after a journalist asked them to say something nice about each other following their previous spat.
According to blog Vulture.com, Minaj was first to answer the question, stating: "I say nice things about Mariah all the time. She is one of my favourite artists of all time.
"To be on a panel with her, it's kind of crazy. All the singers come in aspiring to be Mariah, in terms of talent and in terms of career length."
Carey is then said to have 'flinched' before replying: "That was a very sweet thing to say.
"We did a song that was from my album and it was called, ironically, Up Out My Face. It was one of my favourite songs."
She added: "And I did feel like she was going to go very far and still have that feeling. I am grateful for anything nice that she or anyone has to say."
However, Carey later described it as "a one-sided thing", leaving the Minaj to retaliate: "No, it wasn’t! See? They don’t want a rising star, they want drama."
The Mail adds that throughout the press conference, Mariah and Nicki both 'rolled their eyes' at each other's remarks, while also throwing looks at each other.
Fellow panelist Keith Urban was positioned in between the women in a bid to keep the peace, as Mariah wore a green, strapless dress in comparison to Nicki's glitzy gold frock.
The new series of American Idol is set to premiere in the UK on Thursday, January 17 at 8pm on 5*.
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