Papua New Guinea officials will likely deport Australian Greens Senator Nick McKim after he attempted to visit the asylum seeker camp on Manus Island.

McKim marked the sixth anniversary of Australia's decision to reinstate offshore detention for people arriving by boat.  He went to the East Lorengau camp - one of two facilities holding asylum seekers on Manus Island.  

"The Papua New Guinea Immigration Department took my passport from me and refused to give my passport back and said that in my previous visits I had misreported what has been happening on Manus Island," Senator McKim said.

They returned his passport, but he was approached by PNG police later.  

"I left the gate with my passport and I was walking down the street and a police vehicle stopped me," he said.  "There was one immigration official in that police vehicle and four heavily armed police officers in the vehicle.

"They told me that I had to get in their vehicle. I asked them if they were arresting me and they said 'no' and I then said, 'I'm not getting in the vehicle, I am free to walk down the public street on Manus Island'," he continued.  "The immigration official then said to me it doesn't matter what I do, he will be coming around to my hotel later today to issue me with an official deportation notice."

PNG has not commented on the matter.