"It is a policy clearly that penalises the most vulnerable of all the refugees because people don't really flee by boat from choice, they flee because of some terror in their country of origin," he said.
"To say that Australia will not assist such people under any circumstances is a very substantial statement - it's a change of Australia's values. And I believe an abdication of Australia's responsibilities and... an abdication of our basic humanity."
Mr Rudd, who deposed Julia Gillard as Labour leader and prime minister last month, has been repeatedly attacked by the opposition as soft on refugees.
During his first spell in office, from 2007 to 2010, Mr Rudd ended Australia's practice of transferring asylum seekers to remote Pacific detention centres – but his deal with Papua New Guinea marks a spectacular policy reversal.
"I understand the different groups in Australia and around the world will see this decision in different ways," Mr Rudd said.
"But our responsibility as a government is to ensure we have a robust system of border security and orderly migration on the one hand, as well as fulfilling our legal and compassionate obligations under the Refugees' Convention on the other."
The deal was welcomed by the opposition leader, Tony Abbott, who has repeatedly insisted he will "stop the boats" and has pledged to deploy the Australian navy to turn boats around.
"I welcome it, but it won't work under Mr Rudd," he said. "I think the question that the Australian people have to ask is, who do you trust on this subject? Who do you trust to stop the boats?"
The deal was slammed by human rights groups and the Greens, who said it marked "a day of shame" for Australia.
"This is really an appalling performance from our for the nation and it really does say to the rest of the world that Australia is a very rich country which is prepared to pass the buck to a very poor country because a Prime Minister doesn't have the courage or the moral authority to do the right thing by refugees," said Christine Milne, the Greens leader.
Mr Rudd said the deal with Papua New Guinea will be for 12 months but may be extended. He would not reveal the cost but noted the plan "will not be inexpensive".
Peter O'Neill, Papua New Guinea's prime minister, joined Mr Rudd to unveil the plan in Brisbane, saying it would help his country to prevent illegal immigration. Papua New Guinea, off Australia's north-east coast, has a population of 6.4 million people, with high rates of crime, poverty, disease and corruption.
"Communities like Papua New Guinea and the other island states continue to have challenges of maintaining their borders, and as a result of that we continue to have illegal immigrants into those countries," he said.
"We believe strongly that genuine refugees can be resettled in our country and within the region in the years to come."
Mr Rudd said he had spoken with the UN Secretary-General about Australia convening an international conference to discuss solutions to people smuggling.
"To say that Australia will not assist such people under any circumstances is a very substantial statement - it's a change of Australia's values. And I believe an abdication of Australia's responsibilities and... an abdication of our basic humanity."
Mr Rudd, who deposed Julia Gillard as Labour leader and prime minister last month, has been repeatedly attacked by the opposition as soft on refugees.
During his first spell in office, from 2007 to 2010, Mr Rudd ended Australia's practice of transferring asylum seekers to remote Pacific detention centres – but his deal with Papua New Guinea marks a spectacular policy reversal.
"I understand the different groups in Australia and around the world will see this decision in different ways," Mr Rudd said.
"But our responsibility as a government is to ensure we have a robust system of border security and orderly migration on the one hand, as well as fulfilling our legal and compassionate obligations under the Refugees' Convention on the other."
The deal was welcomed by the opposition leader, Tony Abbott, who has repeatedly insisted he will "stop the boats" and has pledged to deploy the Australian navy to turn boats around.
"I welcome it, but it won't work under Mr Rudd," he said. "I think the question that the Australian people have to ask is, who do you trust on this subject? Who do you trust to stop the boats?"
The deal was slammed by human rights groups and the Greens, who said it marked "a day of shame" for Australia.
"This is really an appalling performance from our for the nation and it really does say to the rest of the world that Australia is a very rich country which is prepared to pass the buck to a very poor country because a Prime Minister doesn't have the courage or the moral authority to do the right thing by refugees," said Christine Milne, the Greens leader.
Mr Rudd said the deal with Papua New Guinea will be for 12 months but may be extended. He would not reveal the cost but noted the plan "will not be inexpensive".
Peter O'Neill, Papua New Guinea's prime minister, joined Mr Rudd to unveil the plan in Brisbane, saying it would help his country to prevent illegal immigration. Papua New Guinea, off Australia's north-east coast, has a population of 6.4 million people, with high rates of crime, poverty, disease and corruption.
"Communities like Papua New Guinea and the other island states continue to have challenges of maintaining their borders, and as a result of that we continue to have illegal immigrants into those countries," he said.
"We believe strongly that genuine refugees can be resettled in our country and within the region in the years to come."
Mr Rudd said he had spoken with the UN Secretary-General about Australia convening an international conference to discuss solutions to people smuggling.