Wyclef Jean -- Fires Donald Trump As a Friend ... F*** Him for Mexico Rant (VIDEO)

Wyclef Jean ripped his old pal Donald Trump for attacking Mexican immigrants ... by dropping an f-bomb on him during a concert.

The ex-Fugees rapper was in Pomona, CA Thursday night when he went off on Trump ... referencing the Presidential nominee's comment that most Mexicans are rapists and drug dealers. Clef's attack was short, sweet, and very telling.

He had appeared on "Celebrity Apprentice" ... doing a guest spot in the boardroom once, and also played a corporate gig for Trump.