SIGNIFICANT progress has been made on the ambitious Trans-Pacific Partnership (TPP) regional trade pact, with "potential landing zones" identified for outstanding items.

This was the latest verdict following the four-day talks at the Grand Copthorne Waterfront Hotel which ended on Tuesday.

"We've made substantial progress here in Singapore," said Singapore Trade and Industry Minister Lim Hng Kiang.

Fresh from the World Trade Organisation's (WTO) historic global trade deal in Bali over the weekend, hopes were raised that the negotiations may be sealed here this week.

The talks had begun in March 2010, with the aim of concluding the three-year negotiations by the end of this year.

But key issues such as those involving market access still remain unresolved.

In a joint statement here on Tuesday, the 12 ministers said: "We have decided to continue our intensive work in the coming weeks towards such an agreement.

"Following additional work by negotiators, we intend to meet again next month."

The TPP nations are: Australia, Brunei, Chile, Canada, Japan, Malaysia, Mexico, New Zealand, Peru, Singapore, the United States and Vietnam. These 12 countries are also Asia Pacific Economic Cooperation (APEC) members.

They account for nearly 40 per cent of global Gross Domestic Product and about one-third of all world trade.

More significantly, the nations are a huge market for Singapore businesses, with 790 million people and total economic output of about US$28 trillion last year.

They account for nearly $300 billion or more than 30 per cent of Singapore's goods trade last year, and includes several key trading partners such as Malaysia, the US, Japan, Australia and Vietnam.