By James Pomfret and Greg Torode
NUSA DUA, Indonesia/HONG KONG (Reuters) - China will likely exploit the absence of the U.S. president at a major Asian regional summit this week to brush off attempts to focus on the South China Sea dispute as Beijing continues to bolster its influence over the strategic waterway.
Any substantive progress in resolving the dispute is unlikely at the East Asia Summit beginning in Brunei on Wednesday and tensions between China and other claimants to the oil- and gas-rich sea will likely linger, analysts, senior regional officials and diplomats said.
The conflicting claims over the South China Sea, stretching deep into Southeast Asia, has pit an increasingly assertive Beijing against smaller Asian nations that look to support from the United States. The row is one of the region's biggest flashpoints amid China's military build-up and the U.S. strategic "pivot" back to Asia.
Washington says it is officially neutral but has put pressure on Beijing and other claimants to end the dispute through talks. It insists all parties refrain from force and do nothing to impede sea lanes that carry half the world's shipping.
U.S. President Barack Obama was scheduled to bring up the South China Sea at the Brunei summit, but he canceled his tour of Asia because of the impasse over the government shutdown in Washington. Secretary of State John Kerry will represent him.
"Overall, it is hard to see how the U.S. can voice these concerns as forcefully and with the same authority without the president there," said Carl Thayer, a South China Sea expert at the Australian Defense Force Academy in Canberra.
"And without Obama, I'm not sure other supporting nations will want to step out in front on this issue, either."
Taiwan, Vietnam, Brunei, the Philippines and Malaysia claim parts of the sea, but China says its territory is marked by a "nine-dash line" that encompasses almost all of the waters. Except China and Taiwan, the other claimants are members of the Association of Southeast Asian Nations (ASEAN), which is hosting the East Asia Summit in Brunei.
Already this week, China has launched a thinly veiled broadside against intervention by the United States in the dispute.
"The involvement of countries not in the region will only complicate this issue and is not beneficial to improving mutual trust in this region," said Vice Foreign Minister Liu Zhenmin. "But there's nothing we can do if people want to talk about it as we cannot muzzle them."
Beijing ultimately wants to settle disputes in the South China Sea through one-to-one negotiations with individual claimants and not multilaterally - a strategy that plays to China's strengths as an emerging superpower with a growing navy and substantial economic and trade leverage over many smaller Asian neighbors.
There have been recent signs, however, of a subtle and sophisticated shift in Beijing's engagement over the sea.
Earlier this year, Beijing agreed to hold tightly choreographed talks with ASEAN on a code of conduct for disputes in the South China Sea, in what Indonesia's Foreign Minister Marty Natalegawa described as "important progress".
"Remember not too long ago, the idea of having any process going on the code of conduct was anathema to China. But now they are where we want them to be in terms of consultations," he told Reuters on the sidelines of another regional summit on the Indonesian island of Bali.
But with Beijing restricting talks to low-level consultations rather than formal negotiations, some diplomats say China may be giving the appearance of dialogue without committing to anything substantive.
The Philippines, which has locked horns forcefully with China over disputed territory, says it had looked for support from its traditional ally Washington for substantial progress on the code of conduct.
"They (the United States) want the code of conduct to be concluded expeditiously but it's really all up to China," said Philippines Foreign Secretary Albert del Rosario.
"I'm hopeful but I can't be sure how this is going to move forward. We're going to have to wait and see."
(Additional reporting by Ben Blanchard in Beijing; Editing by Raju Gopalakrishnan)