Boat bill remove perverse incentive: govt

The federal government expects the coalition to support its plan to strip away the rights of asylum seekers who reach the Australian mainland by boat.

Immigration Minister Chris Bowen expects the opposition to support his bid to excise the Australian continent from the migration zone and deter asylum seekers from trying to reach the mainland by boat.

Mr Bowen will introduce the controversial legislation into parliament on Wednesday after it received caucus approval on Tuesday.

The plan was recommended in the Houston report on asylum seekers and will expand the migration excise zone to the mainland.

It will see rights stripped away from asylum seekers who arrive by boat, paving the way for them to be processed at offshore facilities on Nauru and Papua New Guinea's Manus Island.

Most boat arrivals are picked up in waters between Indonesia and Christmas Island or off the Cocos (Keeling) Islands and asylum seekers rarely make it to the mainland.

Mr Bowen says the bill will remove a "perverse incentive" that could endanger their safety.

"We're trying to save people's lives here," he told Sky News.

"These are difficult decisions for everybody, but we do need to have in place a properly integrated system which says to people there's a safer way of getting to Australia."

The Howard coalition government tried to excise the Australian mainland from the migration zone in 2006, but failed after a backbench revolt led by Liberal moderates.

Mr Bowen says he has spoken to his opposition counterpart Scott Morrison about the proposal and expects the coalition's support when the bill comes to a vote.

Mr Morrison is making no guarantees, saying the coalition will need to see the bill before it decides whether to support it.

"When we see that bill we will take it through our normal procedures as you could expect us to do," he told reporters in Canberra on Tuesday.

Coalition MPs would be free to have their opinions heard on the matter, he said.

"There are a number of members on our side of the parliament who have held consistent views on this issue," Mr Morrison said.

"I would expect any decision they took to act consistently with their long-held principles."

Liberal MP Russell Broadbent said he would urge Opposition Leader Tony Abbott to oppose the plan.

Mr Broadbent was one of the dissenting MPs who opposed the Howard government's proposal in 2006.

He said Labor's plan "completely abrogates" Australia's responsibilities under the United Nations Refugee Convention.

Mr Morrison accused Labor of hypocrisy for deciding to introduce the policy after opposing it while in opposition.

"I am surprised that they have rolled over like little lambs," he said.

Australian Greens immigration spokeswoman Sarah Hanson-Young described the plan as a shameful piece of legislation that discriminated against some of the most vulnerable people in the region.

"This Labor government is now going to try to enact legislation that is so discriminatory and un-Australian that John Howard faced an internal revolt when he tried it in 2006," she said.

Under existing migration laws, only asylum seekers intercepted at sea or at Christmas Island, the Cocos Islands or Ashmore Reef can be sent for processing at Nauru or Manus Island.

Mr Bowen in 2006 called the same plan put forward by the Howard government to excise the mainland from the migration zone "hypocritical and illogical".

"If it is passed today, it will be a stain on our national character," Mr Bowen told parliament in August 2006.

Meanwhile, Mr Bowen on Tuesday revealed the cost of implementing the expert panel's recommendations would be almost $1.7 billion this financial year.

He introduced two appropriation bills to parliament asking MPs to approve the spending.

Mr Bowen's office said the money had all been accounted for in the mid-year budget review released last week.