Stirling naval base in Rockingham is certain to become a major hub for the US military as Washington shifts forces to the Indian Ocean to counter the rise of China and India.
US warplanes will also get greater access to Australian airfields in the North West and Northern Territory as part of efforts to protect valuable trade routes in the region.
US Secretary of State Hillary Clinton and Secretary of Defence Leon Panetta arrived in Perth yesterday to begin two days of talks on security and defence issues.
Defence Minister Stephen Smith confirmed negotiations on giving the US more access to HMAS Stirling would begin officially today.
The Gillard Government has already hinted that the US would be allowed increased use of the naval base, but this week's talks will mark the first time the plan has been discussed at an official forum.
Mr Smith cautioned it would likely be years before it was clear exactly what form the US presence at the base would take.
"But the enhanced importance of Stirling and its utility is to me something that will occur as surely as night follows day," he said.
Australian and US defence officials have looked at Stirling being a "hub" for US forces in the region, with American warships berthing at Rockingham and changing crews flown from the US.
Mr Smith said it was too early to talk about infrastructure needs at Stirling or major dredging to get bigger US warships into the port.
One of the top agenda items is the plan to give the US Air Force wider use of northern Australian air bases and bombing ranges.
The plan could see the US store equipment and even bombs and missiles at Australian bases, or allow Washington to help pay for runways and protective shelters.
In joint meetings amid tight security in Kings Park, Prime Minister Julia Gillard, Mrs Clinton and Mr Panetta will also begin to nut out the legal framework for US and Australian forces to remain in Afghanistan beyond 2014.
Until now, international forces have worked there under a United Nations mandate, but that might become invalid when local forces take control of security and the nature of the mission changes.
Australia has flagged a possible force of 100 special forces troops in Kabul after 2014 but that needs a legal agreement with the US and Afghan governments.