Malaysia will host the summit among 10 Southeast Asian nations and China, Japan and South Korea at the end of this year.

Singapore Foreign Minister George Yeo said after talks with US Secretary of State Condoleezza Rice and other American officials that Washington "has some concerns that the East Asian Summit will be inward looking and exclusive.

"But I told them that countries like Singapore and other countries in the region will also be against that," he told reporters.

The East Asian summit was an initiative of the 10-member Association of Southeast Asian Nations (ASEAN), which since 1997 has been holding summit talks with China, Japan and South Korea at the sidelines of its own summit under a loose "ASEAN plus three" framework.

At their last meeting in November, ASEAN leaders decided to formalize the structure into an East Asian summit. But members were divided over the possibility of expanding the 13-member setting.

The United States has been opposed since 1990 to an East Asian-only grouping, saying such a format would rip apart the Pacific. Analysts said United States was more concerned about China's key role in it and the possibility of Washington's influence in the region waning as a result.

China and ASEAN -- comprising Brunei, Cambodia, Indonesia, Laos, Malaysia, Myanmar, the Philippines, Singapore, Thailand and Vietnam -- have already launched plans for a free trade area that would be the world's biggest duty free zone in six years.

It could blossom into a mega East Asian FTA with participation from Japan and South Korea.

Washington had muscled Japan for nearly a decade against participating in an East Asian grouping mooted by former Malaysian Prime Minister Mahathir Mohamad.

Yeo said that the issue over inclusion of any other countries into the East Asian summit had not been resolved yet, indicating that a decision could be made during an ASEAN foreign ministers "retreat" meeting in April.

Singapore, he said, clearly wanted Australia, New Zealand and India included in the East Asian summit.

Asked on what specific concerns the United States had over the East Asian summit, Yeo said: "I see that the United States is not uncomfortable with the position Singapore is taking.

"They do not want to be excluded in the region."

Malaysia and several ASEAN nations have already hinted they did not want to expand the current East Asian grouping.

They were particularly unhappy over Australia's refusal to sign a Southeast Asian non-aggression pact. Canberra had often echoed US policy of possible pre-emptive strikes against terrorist bases overseas.

The ASEAN non-aggression pact commits signatory states to respect the independence, sovereignty and territorial integrity of all member countries.

Australia's refusal to sign stemmed from fears that such a pact could curb it from commenting on the domestic policies of ASEAN members with which it might disagree, such as human rights abuses in Myanmar.

Yeo said that the United States should continue to play a key role in the region, citing the enormous efforts by the American military in relief efforts during the tsunami disaster that ravaged around a dozen countries located along the Indian Ocean coast.

The United States had deployed 16,000 military personnel, 26 large ships, 58 helicopters and 43 fixed wing aircraft in the relief and recovery effort following the December 26 tsunami that left at least 288,800 people dead.

"There is opportunity now for the United States to strengthen its relationship with Southeast Asia," Yeo said.