Defence Minister Marise Payne has said Australia "will consider" co-operating with Russia in the fight against the Islamic State terror group in Syria as its ally the United States wrestles with its own internal doubts over the fraught question.

Underscoring the awkward position that US allies such as Australia find themselves in as the new administration in Washington crystallises its thinking on some of Donald Trump's more controversial proposals, Senator Payne said the Turnbull government would weigh its options but declined to go into detail.

Australian Defence Minister Marise Payne with the US Secretary of Defence James Mattis.

She was speaking as the Pentagon prepares a plan to ramp up the international effort against the terrorist group, which Senator Payne stressed she did not want to pre-empt.

Asked how comfortable she felt about co-operating with Russia, Senator Payne said in an interview with Fairfax Media: "As matters advance in Syria, these are matters the government will consider but I'm not going to make any further comment on that at the moment."