Heaping the pressure on Labor over its mooted support for a bill that would relax conditions for sick refugees to be transferred to Australia for medical treatment, Mr Morrison said he had seen first-hand "what poorly thought-out changes can do to our borders". He said he was not prepared to compromise with Opposition Leader Bill Shorten on the bill because "its passage in any form takes us backwards". "This is the problem with [Mr] Shorten on national security or borders or anything else - he thinks it's something you trade on," Mr Morrison told the National Press Club. "I'm going to stand on the right ground. You want to join me on the right ground, you're welcome. But I'm not going to find a middle ground.

"You can't split the difference on 1200 deaths [at sea]. You can't split the difference on 50,000 [boat arrivals]. On national security, on border protection, these things are absolutes - and Labor never gets this." Loading Mr Shorten was on Monday receiving briefings from the Home Affairs department and others about the implications of the proposal, which passed the Senate last year with Labor support. The Labor leader is likely to insist on changes that would tighten ministerial discretion. The bill currently gives two doctors the ability to demand refugees on Nauru and Manus Island be brought to Australia for treatment, but gives the immigration minister the ability to require an independent panel review the medical assessment, as well as the authority to overrule any evacuation on security grounds. In his speech, Mr Morrison accused Labor of wanting to "abolish regional processing as we know it", and vowed to never allow the "horrible years" of boat arrivals and deaths at sea to recommence.

"Operation Sovereign Borders has worked. It's delivered a human dividend that is both compassionate and fair," Mr Morrison said. "They have no idea of the consequences of what they are playing with. They will unleash a world of woe again. How do I know? I've seen it before. And I never, ever want to see it again." Hundreds of refugees have already come to Australia from Nauru and Manus Island for medical treatment, but Mr Morrison drew a distinction between these transfers and the transfers that could occur under the legislation before the Parliament. "These transfers have occurred quietly under the existing policy and they have been done by the government, not by anybody else," he said. "The problem with the bill is it takes control from the government, the elected government ... and contracts it out to others who don't have those same interests or responsibilities."