Australia is urging Syria to allow United Nations weapons inspectors access to a Damascus site where a deadly chemical attack is alleged to have occurred.
Prime Minister Kevin Rudd flew back to Canberra on Saturday to receive an intelligence briefing on the escalating Syrian crisis, after reports the United States was weighing up a possible military strike against the Assad regime.
The world is calling for answers amid claims Bashar al-Assad's regime used chemical weapons in an attack on the outskirts of Damascus last week.
"For me it is gut wrenching to see this unfolding," Mr Rudd told reporters in Canberra on Sunday.
"The thought that these sorts of attacks could occur against unarmed civilians ... is like a medieval barbaric scene, rather than something we'd expect on our television sets in the year 2013."
Australia will use its presidency of the UN security council, which it will assume next week, to call for "full and unfettered" access for investigators to the site where the attack occurred.
UN weapons inspectors are in Syria but have not been given permission to investigate the latest claim.
"The burden of proof now lies with the Syrian regime to establish their culpability or absence of culpability on this matter," Mr Rudd said.
He said he had sought information about Australian troops attached to UN missions in the Golan Heights, both on the Syrian and Israeli sides of the border, and troops active on the Lebanese border.
He will also seek reports on other military personnel serving in the region.
"Our concern is of course for their well being," Mr Rudd said.
Defence chiefs have said Australian personnel were trained in handling chemical weapons attacks and were equipped appropriately to handle an attack should there be "any proliferation" of the Damascus incident.
Asked if he had an open mind on any military involvement, Mr Rudd said: "I think it's unproductive and I think it is unwise to begin to speculate on any form of action and what shape that may take."
"The business of responding to an international crisis, as this is emerging as one, is to take it calmly and methodically, step by step."
The prime minister also refused to comment on the appropriateness of US cruise missile strikes against the regime.
"I won't go to the question of military strategy or military tactics," he said.
Opposition Leader Tony Abbott also stopped short of backing military action after receiving a "confidential" briefing on the Syrian situation later on Sunday.
"The important thing is to get to the bottom of what's happened and the best way for that to happen is to allow UN inspectors on the ground to make an assessment," Mr Abbott told ABC TV.
