Asia-Pacific countries negotiating a vast free-trade pact will hopefully secure a deal by the end of this year, US Secretary of State John Kerry said on Friday in Hanoi.
Kerry said the 12 countries negotiating the Trans-Pacific Partnership (TPP) -- including the US, Japan and Vietnam -- had made good "progress" during the last round of talks on the Hawaiian island of Maui last week.
"We are hoping very much that over the course of a couple of months, before the end of the year, (the) TPP can be completed," he told reporters after a meeting with Vietnam's Foreign Minister Pham Binh Minh in Hanoi.
Concerns over labour rights -- Vietnam does not allow independent trade unions -- remain a sticking point for the communist country, but most other issues with Hanoi have now been resolved, Kerry said at a joint press briefing.
Other subjects still being negotiated include Japan's automobile market, as well as Canada's and New Zealand's reticence to open up their dairy sector.
"We will do everything possible to work through these differences," Kerry said.
The top US diplomat has previously praised the TPP -- which will cover nearly 40 percent of the world's economy -- as an agreement that would reap benefits beyond economic growth.
The pact, which excludes China, has been eight years in the making and is vaunted as part of Obama's "rebalance" towards Asia in the face of an increasingly assertive Beijing.
Its aims include raising labour and environmental standards, protecting intellectual property and deterring corruption but critics say the TPP is more about protectionism and corporate benefits than free trade and development.
The TPP countries -- Australia, Brunei, Canada, Chile, Japan, Malaysia, Mexico, New Zealand, Peru, Singapore, Vietnam and the US -- have also been accused of carrying out their negotiations in intense secrecy.
Observers say the delay in securing the deal in Maui last week complicates US President Barack Obama's plans to complete the accord this year with a risk of it becoming dragged into the 2016 presidential election debate.