Morrison says Senate inquiry treating PNG like a colony

IMMIGRATION Minister Scott Morrison has said a Senate inquiry hoping to get inside the Manus Island detention centre was treating Papua New Guinea like a "colony".

Mr Morrison made the comments on ABC Radio on Friday, saying Australia couldn't demand "people turn up and walk around wherever they like".

His comments follow The Greens and Labor this week establishing a Senate inquiry into the circumstances surrounding the riot at the detention centre three weeks ago.

Senator Sarah Hanson-Young on Thursday said the "independent inquiry" was needed, describing government investigations already underway as a "whitewash".

But she also said she hoped senators involved would be able to enter the detention centre for hearings and witness interviews.

The conflicting comments have highlighted the jurisdictional grey area the offshore detention centre sits in, as both the Australian and PNG governments look into the deadly riot.

Mr Morrison on Friday also released his latest Operation Sovereign Borders update, claiming 78 days "since the last successful people smuggling venture to Australia".