AUSTRALIAN air strikes against IS may be expanded from Iraq into Syria in the coming weeks.
Prime Minister Tony Abbott said the government was considering an American request to expand RAAF operations across the border.
"This is a movement of almost incalculable, unfathomable evil," he said.
"It is very important Australia play its role to disrupt and degrade this death cult.
"This is an absolutely evil movement, and the question is if they don't respect the border, why should we?"
Labor leader Bill Shorten said he would decide on the party's support after he was briefed on the proposal next week.
"We will be seeking an explanation of the legal basis. Is it legal what the US has asked us to do?" he said.
Unlike the Iraqi government, the Syrian government has not invited Australia to operate within its borders.
Despite Mr Abbott's comments, government frontbencher Christopher Pyne said a decision on the request was yet to be made. - APN NEWSDESK
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