Mr Morrison, who sits on cabinet's National Security Committee, said on Wednesday that Mr Irvine's warning contained no surprises "in terms of the advice" that the spy chief has been providing to the Abbott government. David Irvine says Australia's terror threat may have to be raised. Credit:Alex Ellinghausen "We are living in very uncertain times the issues in Iraq and Syria are not just occurring there in terms of their potential reach, they can reach countries such as Australia," Mr Morrison told ABC radio. He said that while the terror threat level was set by ASIO and not by politicians, the government had already been acting to improve authorities' ability to monitor who was coming in and out of the country at airports. He said while this had caused delays for passengers security would always be the priority.

"I know that from occasion there may be at times, where a plane can't leave at time or people may be offloaded and that is just putting diligence over convenience," he told the ABC. Later on Wednesday Mr Morrison announced upgrades to the departure advanced passenger processing and airport liaison officer network programs at the National Press Club in Canberra . He said authorities would now screen travellers leaving the country in addition to those coming in and post more officers at international airports to better screen passengers for terror threats before boarding. "It's all about giving us as much heads up, and time, notice and information to ensure we interrogate the likely threats that may be presenting and we have the time to address that," he said. At the Press Club Mr Morrison said the airport measures such as departure e-gates should actually speed up passenger movement.

"What that enables us to do is deal more effectively with the low-risk high-volume traffic and ensure our officers - and we have another 80 counterterrorism unit officers spread across the network - can focus skills and efforts on the

more high-risk possibilities." On Tuesday night, outgoing spy boss Mr Irvine said that the numbers of Australians involved with extremist groups and the influence of the conflicts in Iraq and Syria meant that the threat was continuing to grow. "If we raise it to high, it means an attack is likely. I would say that at the moment, it is at a very elevated level of medium and I'm certainly contemplating very seriously the notion of lifting it higher," he said told the ABC's 7.30 program. His remarks come as Australia prepares to join a likely US-led campaign to beat back the extremist group Islamic State in Iraq and Syria – though Mr Irvine played down suggestions that this would make an attack more likely here. Britain raised its threat level just over a week ago to "severe" in response to events in Iraq and Syria – in particular the beheading of American journalist James Foley by a suspected British radical.

Mr Irvine, who finishes this week as the director-general of the nation's domestic security agency, said he was considering a raise "because of the numbers of people we are now having to be concerned about in Australia, because of the influence of Syria and Iraq on young Australians, both in terms of going to those places to fight, but also in terms of what they are doing here in Australia with a potential intent to attack". Asked whether he might raise the level even in the next few days before he retires, he replied: "It's something that we in ASIO are actively considering." Mr Irvine said Australia was fortunate not to have suffered an attack on its shores in the past and credited security, intelligence and law enforcement agencies for helping make that hapeen. But he added: "We cannot give you absolute guarantees that we can remain as protected as we've fortunately been so far into the future." Also on Tuesday, Prime Minister Tony Abbott spoke with US President Barack Obama by phone and discussed the situation in Iraq, where Islamic State has been cutting a bloody swath through the country's north and west.

Loading It is understood the two leaders agreed to co-ordinate closely on how to destroy the Islamic State, though Mr Obama once again made no specific military requests of Australia. with David Wroe