Here's VIDEO of the moment Dana White broke the news to Daniel Cormier about the Jon Jones fight ... and DC is clearly CRUSHED.
The exchange was captured backstage at the MGM Grand Garden Arena Wednesday night around 8 PM by a UFC camera crew filming for the "Embedded" vlog series.
White told Cormier, "Jones tested positive." Cormier immediately slammed his foot on the ground ... before saying, "I trained so hard."
Dana consoled Cormier ... patting his back, saying, "F***, I'm so sorry."
Cormier asks Dana if there's any way to go forward with the fight, saying, "I'll sign a release."
It's raw and emotional. Check out the clip.