Labor warns of legal issues around Syria

Federal Labor has warned Australia must be "very careful" in ensuring any combat operations in Syria are legal.

Labor MP Nick Champion says unlike the US, Australia is a signatory to the International Criminal Court, meaning any illegal action in Syria could leave Australian soldiers vulnerable to international court action.

The US has a "freer hand" but Australia must ensure it gets the right approvals, he told Sky News on Saturday.

Prime Minister Tony Abbott on Friday confirmed Australia had received a formal request from the US to extend air combat operations to hit Islamic State targets in Syria.

Labor will be briefed on the matter next week and Opposition Leader Bill Shorten says he has asked for an explanation of the legal basis for any extension of the combat mission.

"I have certainly asked Mr Abbott to explain to us the legal basis of what's proposed and the case behind it because these are not matters which should be rushed into," he told reporters in Hobart on Saturday.

Mr Abbott insists Australia will not be rushed into a decision.