Australia's Christian churches are offering sanctuary to 100 asylum seekers caught up in a Government welfare crackdown affecting those who were originally transported to Australia for medical treatment.

Immigration Minister Peter Dutton has said those whose treatment had been finalised would no longer receive financial assistance from the Government.

The asylum seekers have been meeting with Immigration officials over the last two days to discuss cuts to their assistance.

However, if they can find a way to support themselves and their families, they will still have access to Medicare and their children could still attend school in Australia.

Describing the tough stance as "cruel and heartless", chair of the refugee taskforce and the Anglican Dean of Brisbane, the Very Reverend Peter Catt, said religious leaders would not stand by and allow the asylum seekers to become destitute.

"Or cause them to live in terror of being returned to harm on Nauru or Manus Island," he said.

"Among them are pregnant women and women who had suffered sexual assault on Nauru."

'Community will be kind'

Reverend Catt said nine denominations had agreed to open their door across the country if the refugees lost their legal status.

Most had already been stripped of government housing support and had just weeks to find a job or be deported.

Those affected were initially brought to Australia from Nauru or Manus Island for medical reasons.

"When this Government can be cruel, the community will be kind," Reverend Catt said.

"Today we are announcing a number of aid agencies have combined together and are launching a campaign that will see these people supported in the community.

"The sanctuary offer would kick in if the Government sought to remove their legal status or to round them up and to take them back to Nauru and Manus by force."

Huge outpouring of public support in 2016

In February 2016, churches across Australia also united in support of refugees as they faced removal back to offshore detention centres.

Reverend Catt said it precipitated a huge outpouring of public support and he believed it would again.

"We were grateful to the state and territory governments who offered their territories as sanctuaries as well — as did schools and hospitals," he said.

"We are calling on the Government to reverse its decision to cut support to these vulnerable people.

"I could not believe it when I started to hear the stories on Monday morning that Minister [Peter] Dutton would resort to this level of cruelty.

"This Government needs to do something about finding an enduring solution to a problem it has created."

The Australian Churches Refugee Taskforce was established to promote a shared Christian vision of compassion and hospitality for asylum seekers and refugees.

Its members include Baptists, Lutherans, Quakers, Anglicans and the Uniting and Catholic churches.

Concern offer of 'ancient sanctuary' has no legal basis

However, Brisbane Catholic Archbishop Mark Coleridge was concerned the offer of ancient sanctuary had no legal basis in Australia.

"It is from another time and another culture — if others want to do it, then I applaud them," he said.

"As a symbolic gesture, it does have power, but it risks raising unrealistic expectations.

"The important thing is that the Christian community becomes the sanctuary — not a building — and we have been doing that."

Instead, the Archbishop has urged Catholics "to gather around these deeply needy people".

"In this archdiocese, we've been fortunate to work with many, many families who are desperate for a new life in Australia," he said.