'Twilight' Actor Bronson Pelletier -- PEEING in the Airport Terminal!! [VIDEO]

Bronson Pelletier can't deny it anymore -- the 'Twilight' actor definitely took a leak right in the middle of LAX last month ... and there's video to prove it.

In the video, an airport employee approaches Pelletier ... and then he stumbles around, whips out his penis and starts peeing ... for a very LOOONG TIME!

Interestingly, the airport employee stands by patiently waiting for Pelletier to finish ... until police show up to arrest him.

TMZ broke the story ... Pelletier was busted for public intoxication at LAX after getting thrown off a flight for being too drunk.

Witnesses said Pelletier urinated at the gate moments after he was removed from the plane, but the actor had insisted he did no such thing.