A revived threat of Islamic State establishing a foothold in the Middle East and Africa proves the need for laws stopping Australians travelling to volatile areas, the nation's intelligence agency says.
The foreign minister has the power to declare an area a no-go zone and those who travel there could be prosecuted under terrorism laws.
The provisions are set to end in September.
ASIO Director General Mike Burgess said the threat of Islamic State in Africa was not about to immediately increase, but the agency was monitoring the region as there was a good chance it could happen in the future.
"It's a real possibility that we could see the rise of ISIL and ... to have the offence actually would be useful if that situation was to occur," he told a parliamentary inquiry on Monday.
Other enforcement tools such as a temporary exclusion order preventing re-entry to Australia and control orders were all after the fact and the laws were needed to deter people from becoming a threat to Australia, Mr Burgess said.
"We try trying to stop people from going there to gain capability, so I respectfully disagree with those who say it's an unnecessary, over-the-top power," he said.
The Australian Human Rights Commission argued the power was unnecessary as it risked criminalising normal actions, such as people wanting to visit friends or family, do business or retrieve personal property.
There were already other anti-terrorism laws that were able to be used, Human Rights Commissioner Lorraine Finlay told the inquiry, pointing to the fact it was illegal to enter a foreign country to engage in a hostile activity.
The one person convicted under the designated area law was also convicted on the more serious hostile activity charge, she said.
"Deterring and punishing foreign fighters should be done through the longstanding offences relating to hostile incursions into foreign countries and not through a broader offence capturing a range of innocent conduct," Ms Finlay said.
Al-Raqqa in Syria was listed in December 2014 and the Mosul district in Iraq in March 2018. There are no designated zones currently listed.
Four people have been charged for going to a declared area.
On top of the conviction, a second had the charge dropped but faces other charges, a third is before the court alongside other offences and a fourth has only been charged with the declared area offence.
There are "general conversations" about southern Lebanon and Gaza but the government hadn't asked for formal advice on listing new areas, Mr Burgess said.
But he noted people couldn't enter Gaza at the moment and there we no concerns regarding Lebanon.
The Australian Federal Police said it remained concerned about people who travelled to terrorist hotspots without any legitimate reasons.
Questioned on whether the power was too broad and people could inadvertently travel without realising, Assistant Commissioner Stephen Nutt said an area was "by its definition ... a hostile location" and intent needed to be proven.
"We are talking about extreme situations," he said.
"Our experience is that anyone who has gone to a declared area, who has gone to an area where listed terrorist organisations are active, do pose a threat to Australia."
Around 230 Australians travelled to Syria or Iraq to fight for, or support terrorist groups since 2012.
Of those, about 120 are believed to be dead, 55 have returned to Australia and 60 are still in Syria and the region.
