Negotiations over what is set to be the world's biggest free trade agreement resume in Malaysia on Monday with Australia under pressure to relax its opposition to the US proposal that would allow foreign companies to sue sovereign governments.
Japan will join the Trans-Pacific Partnership negotiations for the first time, meaning that with Australia, Brunei, Darussalam, Canada, Chile, Malaysia, Mexico, New Zealand, Peru, Singapore, the US and Vietnam, the agreement would cover nations accounting for 40 per cent of the world's gross domestic product.
New Trade Minister Richard Marles has confirmed Australia will not sign the agreement if it includes a so-called Investor State Disputes Settlement clause that would allow companies who believed an Australian law had harmed their ability to invest to take their dispute to an supra-national body with the power to overrule Australian laws.
But the opposition has indicated it would be prepared to consider such a clause.
"The Coalition would, as a matter of course, put ISDS clauses on the negotiating table and then negotiate ... on a case-by-case basis," Coalition foreign affairs and trade spokeswoman Julie Bishop said earlier this year.
The US is keen to finalise the negotiations before the Asia-Pacific Economic Cooperation forum leaders meeting in Bali in October.
President Barack Obama mentioned reaching an agreement in a phone call to Prime Minister Kevin Rudd in June.
An observer at the talks, Patricia Ranald of the Australian Fair Trade and Investment Network, said Australia was under "enormous pressure" to speed up negotiations and "to agree to unreasonable demands without public debate".