Snoop Dogg has declared a truce with Iggy Azalea ... officially squashing the beef after just one phone convo with T.I.

Snoop just posted a video mea culpa where he says, "No more bad talk. I apologize. I won't do it again." He says the peace treaty was engineered by Iggy's manager ... T.I.

Snoop never mentions Iggy by name during the brief message -- but Iggy immediately accepted the apology on Twitter.