Australian military engagement in Syria will last between two and three years, the defence minister, Kevin Andrews, has said, as the government refused to soften its hardline border protection policies in the wake of the humanitarian crisis.

The prime minister, Tony Abbott, on Wednesday announced that Australia would begin airstrikes in Syria, following an official request last month by the United States to join the air offensive against extremist targets in the region. He also announced that Australia would be resettling an extra 12,000 Syrian and Iraqi refugees in addition to Australia’s overall yearly humanitarian intake of 13,750.

Speaking from Papua New Guinea, where he was attending the Pacific Islands Forum, Abbott made it clear that the government would not consider resettlement exemptions for the Syrian and Iraqis currently in offshore detention.

“There is a world of difference between people in that situation and people who have done a deal with people smugglers to go way beyond the country of first asylum,” Abbott said. “There is just a world of difference and we will never ever do anything that encourages the evil trade of people smuggling.”

“We [Australia] are a country with a good heart, with a big heart as well as a strong arm,” he told reporters.

He contradicted his own defence minister by saying the government did not want to “put a particular timeline” on military engagement in Iraq.

“They’ll be there as long as needed but no longer than necessary,” the prime minister said.

Andrews told the Nine network on Thursday morning that Australians can expect to remain in the region for some time to come.



“We believe that we are probably there for a number of years. But as I said, we review it on a year by year basis,” he told the Today show. “Ultimately, we want to see a peaceful and hopefully prosperous Iraq.”

When pushed, Andrews said that Australian military engagement would last “two, three years”.

“I can’t say for exact terms. But the reality is that this is going to go on for a number of years,” the defence minister said.

He ruled out sending ground troops into the war-torn country, which has been engaged in civil war for four years.

“Do you categorically rule out putting Australian troops on the ground?”, Andrews was asked.

“Yes, I do,” he replied.

Australia currently has 330 troops in Iraq on a training mission to help local troops respond to the threat posed by extremist group Islamic State. Abbott said that that mission would last for two years.

Labor has thrown its support behind the airstrikes, but the shadow defence minister, Stephen Conroy, said the opposition’s support should not be taken for granted.

“This is not a blank cheque; this is recognising the legal basis of going across the border into Syria,” Conroy told ABC Radio on Thursday. “The legal basis for reaching into Syria is confirmed and we are able to degrade those [Isis] forces.”

Labor and the government have argued that there is a claim for collective self-defence in participating in airstrikes in Syria.

Conroy said the Syrian bombing campaign will ultimately help Iraq.

“If degrading Isis forces has an effect that takes a little bit of pressure off the Assad government, well that’s a reasonable price to pay to respond to the authorised request from the Iraqi government to protect the Iraqi people,” Conroy continued. “That’s our mission. It’s not our mission to change the government of Syria, it’s to protect the people of Iraq.”

Gillian Triggs says several Syrian and Iraqi refugees are currently being held in offshore detention. Photograph: Quentin Jones/AAP

The president of the Human Rights Commission, Gillian Triggs, warned that bombing Syria will “almost certainly” lead to more civilian deaths, and an increase in the number of people seeking asylum abroad.

“It is a matter of concern, certainly rather contradictory that on the one hand we’re opening our hearts to Syrian refugees and giving them permanent status, while at the same time we’re embarking on an increased bombing campaign,” Triggs told ABC Radio on Thursday morning.

She has urged the government to reverse its opposition to resettling asylum seekers who have arrived in Australia by boat, pointing out that there are several Syrians and Iraqis in offshore detention.

Taking refugees from United Nations camps, but denying resettlement to asylum seekers in Nauru and Manus Island could be problematic, Triggs said.

“What we’re doing of course is creating a double system that they will not be eligible for permanent residency in Australia even if they are, as we think they will be judged to be, refugees,” she said.

The social services minister, Scott Morrison, who was the architect of the government’s Operation Sovereign Borders when he held the immigration portfolio, said that the government will not budge.

“The government hasn’t made a decision to change our border protection policy. What we’ve decided to do is to respond to a genuine refugee and humanitarian crisis in the Middle East,” he told ABC Radio on Thursday. “Those who have come here courtesy of people smugglers, there is a process in place for those individuals. And those processes will be followed. We’re not reversing our strong border protection policies.”

Australia must be able to choose who is granted permanent resettlement, the foreign minister, Julie Bishop said.

“These are people that we select, these will be people that we screen and will bring to Australia. They’re not people in a people smuggling network selected and provided boats to get to Australia. They are people that we are selecting,” she told Sky News.

A team of Australian officials will be travelling to the Middle East to work with the UN refugee agency and international aid organisations such as the Red Cross and Red Crescent, to start selecting the refugees who will fill the 12,000 extra places.

Labor has urged the government to fill those places within 12 months.

“We do want to have a public clarification from the government ... to make it absolutely crystal clear that those 12,000 places are provided during the course of the next financial year,” the shadow immigration minister, Richard Marles, told reporters on Thursday.