Kelly Clarkson performs at the opening night ceremony of the U.S. Picture: AP

Kelly Clarkson thinks she "acted like a total tool" as she fan-girled over Cher when the pair met for the first time over the weekend.

The 'Piece By Piece' hitmaker couldn't hide her joy recently when she finally met the pop superstar, and she has admitted she still feels like a kid again when it comes to enjoying music and meeting other singers.

Explaining how she gets just as excited with her fellow judges on 'The Voice', she told Extra: "I'm a weirdo, I acted like a total tool! I'm a genuine fan of people.

"Even [Adam Levine], I was a genuine fan, he puts on an awesome show. I love going to see [Blake Shelton], I love artists. I love anybody being creative in their own way and what they're doing. I'm still a 10 year old about that, and I hope I always am."

Kelly, 36, had been interviewed on the red carpet at the Kennedy Center Honors in Washington, D.C. over the weekend when she spotted Cher, 72, behind her and made sure to introduce herself.

She told the 'Believe' singer that she's a "big fan" before telling herself to "stop talking" as she started to race through her words.

She gushed: "Hi! I'm Kelly Clarkson! Nice to meet you! I have never met you, I've been talking about you this whole time going, 'She's right behind me!'

"I'm a big fan, obviously everyone here is, I'm gonna stop talking. OK, yeah, I get very nervous."

Cher seemed genuinely pleased to meet Kelly too, and smiled as the star showed just how much it meant to her.

She said: "I'm so happy to meet you!"