Another DUP councillor is expected to resign because of his opposition to the party going into government with Sinn Fein.
Ian Paisley and Martin McGuinness have been getting along well
Mel Lucas, who was suspended by the DUP at the weekend, is expected to confirm his decision at a meeting of Antrim Borough Council.
Mr Lucas was a DUP candidate at the last assembly elections.
He also recently called on South Antrim MP William McCrea to resign claiming he had broken his election promises.