Ahead her performance at The White House last night, US President Barack Obama has said that he loves Katy Perry and that she is one of his "favourite people".
At a dinner to mark the 46th anniversary of the Special Olympics, Obama introduced Perry to the stage saying: "We have just one of my favourite people performing tonight - Katy Perry. We are so grateful to her.
"I love Katy Perry. She is just a wonderful person. I've met her mom and now I know why she is such a wonderful person, but I just want everybody to know she is on tour right now and so for her to take time out to do this is really special, and so we really want to say thank you to her for doing this."