The small island just north of PNG's mainland began erupting last month, prompting the evacuation of over 600 residents to the East Sepik capital Wewak.
According to the Rabaul Volcano Observatory, Kadovar's eruption continues at a low-level with mild steaming at the summit, and gentle emission of lava.
But Governor Allan Bird said he has had to tell the resettled Kadovar community that a return was not viable.
He said they had accepted the sad news.
