AUSTRALIA will continue to work with the US to "degrade and destroy" Islamic State, despite the Turnbull Government rejecting a US request to boost its military involvement in the Middle East. 
Ory Abramowicz, a spokesman for the State Department's Bureau of East Asian and Pacific Affairs, said Australia had been one of its most valued partners and a leader in the fight against IS.
"It is up to each country to make its own decisions about how it can contribute to the ... campaign," he said.
The comments come after US Defence Secretary Ash Carter wrote to coalition partners seeking more military help in the wake of the Paris terror attacks last year.
However, Federal Defence Minister Marise Payne formally rejected the request, saying Australia was already making a "substantial" contribution that was under ongoing review.
"The Government has advised Secretary Carter that our existing contributions will continue," a spokesman for Senator Payne said.
While some conservative MPs are pushing for Australia to ramp up its involvement, Opposition Leader Bill Shorten called on the Government to maintain a bipartisan approach to defence policy.Australia currently has about 780 troops in the region conducting air strikes and military training.