Immigration Minister David Coleman says Australia's offshore processing of asylum seekers would fall apart under changes to medical transfers.
Proposed changes to the way sick asylum seekers are transferred to Australia are designed to end the nation's offshore processing system, according to Immigration Minister David Coleman.
But Labor - which has supported the changes - has rejected the claim, saying offshore processing is here to stay if it wins the next election.
Under reforms to medical transfers that have passed the Senate with the backing of the opposition and crossbenchers, two specially-appointed doctors could request medical transfers for offshore asylum seekers to Australia.
A minister would then be required to review their case in 24 hours, and if they reject it, an independent health advice panel would review it.
Despite Labor stressing the panel's advice could still be overruled by a minister on security grounds, Mr Coleman said the laws are designed to allow every asylum seeker detained offshore to be sent to Australia.
That would undermine the nation's offshore processing system and ultimately lead to its demise, he said.
"Within weeks, it is highly likely - and that's the advice that we've received - that substantially everyone who is currently on Manus and Nauru would come to Australia," he told Sky News on Sunday.
"The structure of this legislation is designed to undermine offshore processing to such a state that it no longer exists any more."
The minister dodged questions about whether that suggests everyone in the offshore processing centres is unwell.
But Mr Coleman said the current process was effective, with doctors located at offshore processing sites recommending transfers which are then considered by the government's Department of Home Affairs.
Defence Minister Christopher Pyne echoed these points on Sunday, telling the ABC the bill could see 1,000 refugees transferred to Australia.
"The bottom line is, we're not prepared to weaken border protection," he said.
The coalition announced this week it would establish an independent health panel, which could ask bureaucrats to review individual cases, as an extra layer of oversight.
Opposition immigration spokesman Shayne Neumann accused Mr Coleman of being a "shrill liar", saying Labor would never let people smugglers back in business by giving way on offshore processing.
"We will continue strong border protection measures including offshore processing, turnbacks when safe to do so and regional resettlement," he told AAP on Sunday.
"These amendments are about making sure sick people in regional processing facilities can receive the medical care they need, without compromising our strong border protection arrangements."
Despite the war of words, Labor says it is searching for a "middle ground" with the government.
A vote is expected on the changes in the lower house as early as this week, with the minority coalition government facing the prospect of a loss if both Labor and enough crossbenchers support them.
But Labor leader Bill Shorten appeared to back away from it on Friday.
"I do think if there's middle ground, we should try and find it," he told reporters in Sydney.