But US Trade Representative Michael Froman, in a statement on behalf of the 12 countries involved, insisted that "significant progress" had been made on the Trans-Pacific Partnership (TPP) agreement.
"After more than a week of productive meetings we've made significant progress and will continue on resolving a limited number of remaining issues, paving the way for the conclusion of the Trans-Pacific Partnership negotiations," Froman told a press conference.
The negotiators were "more confident than ever that TPP is within reach," he said, adding that the Pacific Rim countries involved would continue to have bilateral discussions to try and iron out their remaining differences.
The TPP -- already eight years in the making -- is the most ambitious trade deal in decades, a vast free-trade bloc encompassing 40 per cent of the world's economy and part of Obama's much-vaunted "rebalance" towards Asia in the face of an increasingly assertive China.
More From This Section
China, notably, is not included.
The press conference was delayed by several hours as countries including Australia, New Zealand, Japan and Canada attempted to thrash out a deal yesterday in what had been billed as the home straight.
The 12 countries involved have faced criticism for carrying out their negotiations in what opponents have charged is a high level of secrecy.
Critics say the proposals indicate a deal moving more toward protection than free trade; one more about corporate benefits than boosting economies and development.
But backers say the modern global economy needs a new framework of rules to protect intellectual property-dependent 21st century industries that aren't covered in traditional free trade pacts like the World Trade Organisation.