B ANGKOK - The United States, China and the European Union opened talks on July 25 with 15 Asia-Pacific countries, aiming to forge a new framework for peace and regional security in the post Cold-War era.

The inaugural one-day ministerial talks, an initiative of the Association of Southeast Asian Nations (Asean, started without a number of the countries at the center of the region's potential flash points.

The new 18-nation Asean Regional Forum (ARF), described by the United States as an ideal vehicle for lowering regional tensions, will focus on issues involving North Korea, the disputed Spratly Islands, Burma and Cambodia, forum sources said.

But the Pyongyang, Rangoon and Phnom Penh governments were not represented. Neither was Taiwan, one of six claimants to the Spratlys, a potentially oil-rich chain of islands in the South China Sea.

Thailand, the forum host, will reaffirm in the forum's final statement Asean's belief that ARF "could make a significant contribution to security through preventive diplomacy", the sources said.

It will also commit all participants to meeting on an annual basis and set next year's talks for Brunei, they said.

Cambodia said on July 23 it wanted to attend the forum next year and Asean has already established what it calls a "constructive engagement" with Burma.

Asean established the forum as a first step in taking a more forceful role in ensuring peace and security in its region. US officials said it dovetailed with President Bill Clinton's emphasis on regional cooperation.

They provide a forum for nations that have been historic rivals and are potential enemies to directly convey to one another their intentions, he said.

Senior US officials said they hoped the forum would reaffirm support for the Cambodian government with a commitment to cut off the Khmer Rouge .