EXCLUSIVE

The entire cast of "Real Housewives of Atlanta" -- minus one -- is threatening to walk off the show if Porsha Williams is fired over her fight with Kenya Moore.

The one holdout -- Kenya Moore.

Sources close to the show tell us the women hatched their plan this weekend at Kandi Burruss' wedding ... telling the show's producers how much they despise Moore because of all the drama she stirs up.

As we reported ... Williams attacked Moore during taping of the reunion special ... and producers may use the bitch fight as justification for giving Porsha the axe.

We're told since the brawl, ALL housewives' contracts for next season have been put on hold -- until show honchos figure out what to do with Porsha.