Greens Immigration spokesperson Nick McKim says the decision to bar him from visiting Australia's Manus Island detention centre continues the disgraceful secrecy of the Australian government's policies.

"This is a deeply disappointing decision that shows the utter determination to keep a veil of secrecy around Australia’s detention centres and the Good Friday attacks," Senator McKim said.

"People are being warehoused as far from scrutiny as the Australian government can hide them."

"It would not surprise if Peter Dutton has his fingerprints on the decision."

Evidence presented to the Senate inquiry into the conditions on Manus Island and Nauru should prompt the immediate closure of both offshore detention centres, Greens Immigration spokesperson Nick McKim says.

"Australia’s centres on Manus Island and Nauru are inhumane, non-compliant with international obligations, and should immediately be closed and all detainees brought to Australia," Senator McKim said.

Peter Dutton has been caught out lying about people seeking asylum on Manus Island and must resign or be sacked, Greens Immigration spokesperson Nick McKim says.

"Statements from Papua New Guinea police have exposed Mr Dutton’s lies. This has disturbing echoes of the children overboard scandal," Senator McKim said.

"This was an outrageous lie designed to pour scorn on the people he has left stranded on Manus Island."

Peter Dutton and Malcolm Turnbull's rolling citizenship announcements are a transparently desperate attempt to win back votes from Pauline Hanson and appease the far right of the Liberal Party, Greens Immigration and Citizenship spokesperson Nick McKim says.

"We should be bringing people together, not dividing them through patronising citizenship tests and unnecessary waits for permanent residency and citizenship," Senator McKim said.

"The real problem here is that Peter Dutton's values are not mainstream Australian values. 

The Manus Island detention centre is unsafe and should be closed with all detainees immediately brought to Australia.

"We have responsibility for the lives and safety of detainees and staff alike. Prime Minister Turnbull must act," Greens Immigration spokesperson Senator Nick McKim said.

"Some of the shots fired last night hit accomodation buildings. It is blindingly obvious that it's an unstable and dangerous environment and Australia has to step in."

"We created the problem. We have to solve it."

All of Australia's detainees on Manus Island must be brought to Australia, Greens Immigration spokesperson Nick McKim says.

"The people the Australian government have locked up on Manus Island have suffered immense physical and psychological harm," Senator McKim said.

"Immigration Minister Peter Dutton's plan to just leave them to languish on Manus Island is unfair and unconscionable, and shows his determination to extend the humanitarian crisis for as long as he can."

Amnesty International's report on the profit-making of Broadspectrum from Australia's detention centres on Nauru is a warning to companies considering bidding for contracts that they do so at considerable risk to their brand and reputation.

"Any companies who sign contracts to run the camps will immediately become complicit in torture," Greens Immigration spokesperson Senator McKim said.

The Australian Government must immediately rule out sending persecuted Hazara people back to Afghanistan, Greens Immigration spokesperson Nick McKim says.

"The Hazaras are one of the most persecuted peoples on earth, and continue to be targeted across Afghanistan," Senator McKim said.

"There are several thousand Hazara people currently in Australia who have a legitimate fear of persecution if they are forcibly returned to Afghanistan."

"Malcolm Turnbull must rule out sending Hazaras to Afghanistan."    

Immigration Minister Peter Dutton must immediately clarify the status of medical care available to people seeking asylum on Manus Island.

"We are hearing that there are no doctors working today in the detention centres on PNG due to International Health and Medical Service failing to properly register its medical practitioners with the Papua New Guinean government," Greens Immigration spokesperson Senator Nick McKim said.

"If this is true, Mr Dutton must take urgent action to ensure proper medical care is available to people who remain Australia's responsibility." 

The government's improper management of Australian Border Force's statutory powers is squarely the fault of Immigration Minister Peter Dutton.

"This government has grabbed for itself a massive range of new powers in its process of militarising the Department of Immigration and Border Protection," Greens Immigration spokesperson Senator Nick McKim said.

"The failure of the Department to ensure that these powers are being used legally falls squarely on the shoulders of the incompetent Peter Dutton."