During an appearance on Jimmy Kimmel Live! on Thursday night, the All I Want for Christmas is You singer was asked if she had read what Britney wrote about her in The Woman in Me, which was released in late October.

"I heard something about it," she replied. "I love her actually."

Jimmy then produced a copy of the autobiography and read a passage in which Britney recalled meeting Mariah backstage at an awards show and she had "the most beautiful otherworldly light".

Reacting to the mention, Mariah said, "That was super sweet what she said about me."

In the book, the pop star wrote, "At one awards show, I knocked on Mariah Carey's dressing room door. She opened it and out poured the most beautiful otherworldly light. You know how we all have ring lights now? Well, more than twenty years go, only Mariah Carey knew about ring lights. And no, I can't say just her first name. To me, she is always going to be Mariah Carey."

Mariah confirmed that "of course" she had a ring light - which casts an even light on its subject - more than 20 years ago.

In the rest of the passage, which Jimmy did not read out, Britney recalled Mariah teaching her about lighting when they took a photo together.

"I did everything that Mariah Carey told me to do and we took the photo. Of course she was completely right about everything - the photo looked incredible," she gushed. "I know I won an award that night, but I couldn't even tell you what it was. The perfect photo with Mariah Carey - that was the real prize."