Christina Aguilera — Disneyland Tantrum … Calls Mickey an A**hole

EXCLUSIVE

Christina Aguilera is not in the Christmas spirit … she spent her birthday last week in “The Most pleased Place On Earth” … in a heated argument with Mickey Mouse … TMZ has learned.

Our theme park source tells us while ringing in her 34th b-day at Disney’s California Adventure, Christina and her crew tried to get a pic with Mickey, but he was going on a break … so Christina was told she had to wait. Cue meltdown!

Aguilera lost it, and called Mickey an “a**hole.” We’re told she even dropped the dreaded, “Do you know who I am?”

Xtina’s crew started hurling threats, we’re told … and Mickey had to be ushered to a safe zone — out of public view. Security was called, but by the time they arrived … the former Mouseketeer had already split. 

Aguilera’s rep had no note.