"The United States government has requested that Australia help to transport stores of military equipment, including arms and munitions, as part of a multi-nation effort," Australian Prime Minister Tony Abbott said in a statement.
"Royal Australian Air Force C-130 Hercules and C-17 Globemaster aircraft will join aircraft from other nations including Canada, Italy, France, the United Kingdom and the United States to conduct this important task."
The announcement came as Australia joined the US military in dropping humanitarian aid to the besieged Iraqi town of Amerli, where thousands of Shia Turkomen have been cut off by jihadist rebels from receiving food, water and medical supplies.
Australian Defence Force chief Mark Binskin said at a press conference that 15 pallets of food, water and hygiene packs - enough for 2,600 people for a day - were dropped by a C-130 earlier Sunday.
He added that the delivery by Australia of arms and munitions "from Eastern Bloc countries" to the Kurdish peshmerga would take place "in the coming days", and in their case would involve handovers on the ground rather than airdrops.
"We want to make sure that we know where the arms... and the munitions go when we deliver, so at this stage there won't be a drop. We'll be landing and handing them over to officials from the peshmerga," Air Marshal Binskin said.
Albania, Croatia and Denmark have also committed to providing Kurdish forces with arms and equipment, the US said Wednesday.
Abbott said there was a "humanitarian catastrophe" in Iraq and Australia was working with other countries to alleviate it and "address the security threat posed by ISIL".
Amid criticism by the Greens Party over the country's increased involvement in Iraq, the Australian leader stressed that "there is no role envisaged for combat troops on the ground".
"None of us want to get involved in another Middle Eastern war. But it is important to do what reasonably can be done to avert potential genocide," Abbott said.
"Any military activity by Australia over and above the humanitarian airdrops and the military airlift that we've talked about now will be... along with allies and it would be at the request at the government of Iraq.
"But no specific request has been made, no specific decision has been made."
Australia was also involved in airdrops earlier in August to refugees in northern Iraq to deliver humanitarian assistance.
The Iraqi government is struggling to retake large parts of the country after a lightning militant offensive led by the IS, also known as ISIL and ISIS.
The jihadis seized Iraq's second city Mosul in June and swept through the country's Sunni heartland as security forces fled.
The US military said Saturday it had launched fresh attacks against IS forces in Iraq, with fighter aircraft and drones used to carry out strikes near the Mosul dam.
