Asia-Pacific leaders yesterday promised greater efforts to realize free and open trade and investment in the region, and appealed for an end to the nuclear crisis on the Korean Peninsula.

Leaders of the 21-member group adopted the Hanoi Declaration after concluding the two-day meeting, in which they vowed to increase energy security.

They also released an oral statement on the Korean Peninsula nuclear issue before donning traditional Vietnamese silk ao dai tunics for a photo session.

Leaders agreed to promote regional economic integration, but put off the US-backed idea of creating an APEC-wide free trade zone until 2007.

"We instructed officials to undertake further studies on ways and means to promote regional economic integration, including a Free Trade Area of the Asia-Pacific as a long-term prospect," said the declaration.

The group, representing roughly half of world trade and nearly 60 per cent of the world economy, reaffirmed support to jump-start the Doha Round of global trade talks.

"The consequences of the failure of the Doha Round would be too grave for our economies and for the global multilateral trading system," it said.

Participants are determined "to continue efforts to combat terrorism in every form," but said "any measures taken to combat terrorism must comply with our international obligations."

President Hu Jintao told the meeting in the morning that terrorism should be tackled with a comprehensive strategy. "We should tackle both the symptoms and the root cause," said Hu, calling for removing the breeding ground for terrorism.

The APEC leaders also discussed co-operation on coping with pandemic diseases, the fight against HIV/AIDS, and emergency preparedness and disaster response.

They said energy security is "critical for sustainable economic development" and urged member economies to facilitate energy investment and cross-border energy trade, to develop new and renewable energy sources and technologies to ensure cleaner use of fossil fuels and to boost energy efficiency and conservation.

The declaration did not include the nuclear issue on the Korean Peninsula, which was a focus of attention at the APEC forum.

Leaders released an oral statement, which expressed "strong concern" about the Democratic People's Republic of Korea's (DPRK) nuclear test last month.

It called for full implementation of UN resolutions against the DPRK and urged Pyongyang to fulfil a September 2005 agreement that committed it to give up nuclear arms in return for security and aid guarantees.

Founded in 1989, APEC is a major regional forum for promoting open trade and practical economic and technical co-operation in the Asia-Pacific region.