The head of the US Seventh Fleet believes it won't be long before Australia and America join with China for three-way naval exercises in the Pacific.
The comments from Vice Admiral Scott Swift come at the start of one of the biggest joint Australian-US military exercises, known as Talisman Sabre.
Vice Admiral Swift sailed in to Sydney Harbour on Saturday on board the USS Blue Ridge to command the training activity.
Talisman Sabre is a biannual military exercise but it has gained even more significance as the Obama administration continues its so-called pivot to the Asia-Pacific.
The ABC reports Vice Admiral Swift said this refocus should not be seen as simply as an effort to contain China's regional ambitions.
He said it will not be long before China is included in the regional war games and three-way exercises including the United States, Australia and China are likely.
"Absolutely, it's a foregone conclusion. The question is when it occurs and I think it will occur much sooner than anyone is predicting," he said.
Talisman Sabre begins on Sunday when a total of 27,000 US and Australian troops will be involved in various military exercise throughout the Pacific over the next two weeks.