The Greens will move to amend Australia's visa laws to give Parliament the power to block foreign leaders from visiting Australia on the grounds of character.

"Parliament is sovereign in this country," Greens Immigration spokesperson Senator Nick McKim said

"Consistent with our position that Parliament should have the final say on Australia going to war, we believe that Parliament should have the right to refuse entry to, or deport, foreign leaders on the basis of their character."

"This issue has been crystallised for us by Donald Trump becoming US President."

The Greens welcome the united front from the long list of community groups and organisations calling for immediate action on offshore detention.

"The situation on Manus Island and Nauru is completely untenable," Australian Greens immigration spokesperson Senator Nick McKim said.

"Resettlement for any refugees in the US now looks extremely unlikely and Prime Minister Turnbull needs to immediately close the camps and bring every man, woman and child in offshore detention here to Australia."

Malcolm Turnbull should scrap his refugee "deal" with the US and bring people detained on Manus Island and Nauru to Australia , Greens Immigration spokesperson Nick McKim says.

"It is becoming increasingly clear that Mr Turnbull is placing his faith in a xenophobic and anti-immigration US President who has a track record of dishonesty and lies," Senator McKim said.

"Only a fool would take Trump at his word."

Malcolm Turnbull should end the uncertainty and confusion over the US refugee "deal" and bring the people to Australia, Greens Immigration spokesperson Nick McKim says.

"It is now clear that the US deal relies on an unhinged, dishonest President," Senator McKim said.

"People should be very concerned about what Mr Turnbull is prepared to do to get this deal done."

"As we now know, the deal does not commit the US to accept a single person."

Immigration Minister Peter Dutton must immediately intervene so a pregnant woman on Nauru suffering serious health problems can receive medical assistance, Greens Immigration spokesperson Nick McKim says.

"I have today written to Mr Dutton seeking his urgent intervention in this case," Senator McKim said.

"Medical specialists have demanded that she be immediately brought to Australia to receive the care she so desperately needs."

"It is really sad that we need to ask the Immigration Minister to show basic humanity to people who are in his care."

Peter Dutton must be sacked and his department cleaned out because of ongoing and serious human rights abuses and financial maladministration, Greens Immigration spokesperson Nick McKim says.

"The latest audit has uncovered years of maladministration at the Department of Immigration and Border Protection, and the Minister needs to take responsibility," Senator McKim said.

The release of another scathing audit of the Department of Immigration and Border Protection confirms Peter Dutton has lost control of his portfolio and its budget, Greens Immigration spokesperson Nick McKim says.

"What a bloody shambles," Senator McKim said.

"This audit confirms that $1.1 billion of taxpayers' money was spent without proper authority, while there is no record of who authorised the spending of a further $1.1 billion." 

"This is yet another indictment on Minister Dutton's capacity to manage the taxpayer dollars he has been entrusted with."

The four companies that have expressed an interest in multibillion-dollar government contracts for detention centres on Manus Island and Nauru should be aware of the reputational harm  of being associated with policies of cruelty and harm.

A Senate estimates question on notice from Australian Greens Immigration spokesperson Nick McKim revealed Serco, Decmil Services, Canstruct and Ostwald Bros have expressed interest in taking over the major contract for Australia's offshore detention centres.

Immigration Minister Peter Dutton's proposed visa changes are deeply xenophobic and a continuation of his attack on multiculturalism in Australia.

"This nothing less than a blueprint to return our country to the divisive days of the White Australia Policy," Greens Immigration spokesperson Nick McKim said.

"As the Department of Social Services noted, this proposal will 'undermine Australia's social cohesion' and create a two-tiered society."

"This will increase the risk factors that cause violent extremism."

The UNHCR has told an inquiry into allegations of abuse in Australia's offshore detention centres that the government's policies are undermining the global refugee system.

"The UNHCR have made it clear that by denying refugees access to Australia, the government is weakening the international framework to resettle refugees," Greens Immigration spokesperson Senator Nick McKim said.

"They have submitted that Australia has deliberately exposed people to harm, and failed to meet our legal obligations."