Gwen Stefani has called Christina Aguilera "all girl power".

Gwen is joining the US version of The Voice as a judge and will be joined on the panel by series stalwarts Adam Levine and Blake Shelton, as well as fellow newcomer Pharrell Williams.

Previously, Christina and Colombian singer Shakira were involved, with Christina giving Gwen a lot of tips before she took the reins.

"With Christina, she wrote me this really sweet note like right when it was all going down," Gwen told Access Hollywood.

"Then she ended up coming over for [my son] Kingston's birthday party and brought over [her son] Max. It was just like, 'Yeah!' She was all girl power.

"[She said,] 'You gotta be like this and you gotta do that,' and she was like, 'You're gonna love it! You are gonna be fine, you're gonna be fine. She was really sweet to me."

Once it was confirmed that Gwen and Pharrell would be joining the next season of the show, they showed their excitement by taking to the stage during the last series. They performed a rocking version of their hit Hollaback Girl, with Gwen briefly getting to have a chat with Shakira too.

"I met her when I got to do Hollaback Girl with Pharrell [on the show] that time, and it was just a second. I got to see her baby and oh my God, the baby is so beautiful!" Gwen gushed.

It seems more performances could be in the pipeline for the singer, who would love to get her band No Doubt involved in the show. She would love to have them perform together on an episode, as it would be like the two parts of her life coming together.

The star has already made her new job a family affair, as earlier this week she confirmed her husband Gavin Rossdale will be joining her as an adviser.

"He is super articulate and he has a really good opinion and he is smart and he's been doing a really good job," she said.