Trade Minister Tim Groser says progress on talks to create a Pacific-wide trade region will hinge on Japan and the United States.
Mr Groser is in Singapore for a ministerial meeting on the controversial 12 nation Trans Pacific Partnership (TPP) over the weekend.
The TPP has been dogged by questions about the size of the economic gains it might yield, demands for greater public scrutiny, and leaks that have highlighted significant differences between America and other nations.
Patent and copyright protection and environmental standards are reported to be topics on which the US and other nations disagree.
Mr Groser says if discussions between the United States and Japan on market access for goods such as cars and dairy products succeed, that will give impetus to the talks, but if they fail, he believes the negotiations will drag on.