​Malcolm Turnbull is under pressure from key figures within the Coalition and crossbench senators to heal the "weeping sore" of Australia's treatment of asylum seekers on Manus Island and Nauru.

Human Rights Commission president Gillian Triggs, is also seeking a meeting with the Prime Minister to press the case for policy change, describing the situation as unsustainable on practical, financial, legal and moral grounds.

"You simply can't warehouse people for these lengths of time without a solution," said Professor Triggs, who was frozen out by former prime minister Tony Abbott.

Liberal MP Russell Broadbent has implored Mr Turnbull to act, in the first instance by removing children from Nauru. Mr Broadbent is the last MP from the group of Liberals who forced John Howard to soften his border protection policies in 2006.

"You know what happens to a weeping sore if you don't deal with it. It becomes a raging ulcer," he told Fairfax Media.

Another member of that group, Judi Moylan, who retired form politics at the previous election, has joined 5000 women including businesswoman Janet Holmes a Court in petitioning Mr Turnbull to end abuse of those in detention on Manus and Nauru.

"Many women across Australia understand only too well what it is like to live in fear of violence and sexual assault," an open letter by the women says. "That's why we can no longer watch in silence as some of the world's most vulnerable people confront that horror in the twilight world of Australia's detention centres."

Fairfax is aware of other Coalition MPs who have raised the issue with Mr Turnbull.

Several Senate crossbenchers say their attitude to the new government will be influenced by the response from Mr Turnbull, who this week said he shared the concerns of others about those on Nauru and Manus Island.

More than 650 asylum seekers, including 93 children, remain in detention on Nauru, while 936 men are being held in the Manus Island detention centre.

More than 50 others have been transferred to a low-security transit centre on Manus after being recognised as refugees, but they have no right to work for pay, or freedom of movement.

Fairfax Media has just returned form the island, where several of those in the transit centre said the situation was hopeless and that they would prefer to return to the detention centre, where sedatives were distributed to those with mental health issues each night.

While Mr Turnbull has ruled out any prospect of refugees on Nauru or Manus being resettled in Australia, he is being urged to consider other resettlement options and what can be done to tackle self-harm and abuse.

"It can't be that there is no resolution for these people. If you have a view that they are never going to be settled here, you have got to find an answer," Mr Broadbent said. "How long will the churches put up with this? How long will people who care put up with this?"

Tasmanian independent senator Jackie Lambie said Mr Turnbull had to deal with the issue.

"This has been simmering under the surface and it's about to explode, and I don't think he's got any choice but to deal with it," Senator Lambie said. "We have damaged them and to continue to leave them in detention – I don't think that's a very good option."

Other crossbenchers planning to raise the issue with Mr Turnbull include Victorians Ricky Muir and John Madigan.

Senator Muir said he welcomed Mr Turnbull's statement about sharing the concerns of Australians regarding those on Manus and Nauru.

"I recognise that any changes to Australia's border protection policy will need to be made by cabinet, but I'll be discussing the conditions on Manus Island and Nauru when I meet with the Prime Minister," he said.

Senator Madigan said he intended to raise the issue with Mr Turnbull, who has signalled a willingness to engage more closely with the crossbench than Mr Abbott.

"For some people it's out of sight and out of mind, but we're footing the bill for this; we've got some responsibility."

Palmer United Party leader Clive Palmer said he would raise with Mr Turnbull the need to end abuse and improve transparency on Manus and Nauru.

"We can't continue to suppress what is happening; it's happening in the name of all Australians," he said.

Professor Triggs said the treatment of those in detention contradicted the "wonderful, open-hearted" decision to resettle 12,000 refugees from Syria and northern Iraq.

"I understand the Prime Minister will want proper consultation and to think about this, but the truth is, in the longer term, it is simply unsustainable," she said.

"There has to be a rethinking of the policy. We have to find some equitable way of dealing with those who have fled persecution."

Professor Triggs said she was particularly concerned about the plight of a Syrian father of five who is believed to be being held on Christmas Island after a prolonged stint on Nauru.

Greens senator Sarah Hanson-Young said that with a new prime minister came a chance for change.

"Instead of renewing the management contracts for these camps of cruelty, costing us billions of dollars, the government should read the writing on the wall and simply shut them down."

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