Photo: Is Christina Aguilera Adele's Biggest Celeb Fan?

The 'Someone Like You' singer hooks up with Xtina on tour.

At her LA gig, Adele was approached by her new BFF (Biggest Famous Fan) Christina Aguilera for a photo.

So excited with her photo opportunity, Christina posted two snaps of the singers together on her Twitter.

"Someone Like You is my favorite! Beautiful to see all her fans sing it tonight! ;) love u Adele," she wrote.

"Another with Adele after LA show. Love her!..."

As well as Christina hanging out in the crowd, Twilight's Robert Pattinson and the cast of Glee also showed up to sing along to Adele's huge hits.

Check out Adele and Xtina in their photos below...