US Secretary of State Hillary Clinton will warn against the use of force between China and its neighbors on a tour of Asia that comes amid mounting tension over sea disputes, officials said Tuesday.

On her third visit to Asia since May, Clinton will become the first US secretary of state to take part in a summit of Pacific islands -- an area where China's influence has been growing -- and to stop in East Timor.

Clinton will hold talks in Beijing on September 4 and 5, the United States and China announced. Friction has been rising both in the South China Sea, where Beijing is building a controversial new garrison, and in the East China Sea, where activists have sailed to islands claimed by both Japan and China.

"We don't want to see the disputes in the South China Sea, or anywhere else, settled be intimidation, by force. We want to see them settled at the negotiating table," State Department spokeswoman Victoria Nuland said.

Nuland called for military transparency by China and said Clinton would seek progress on an elusive goal of setting up a code of conduct to manage conflicts in the South China Sea, through which half of global cargo flows.

"We continue to think that that's the best way to address these disputes, so I think you will see it come up on many of these stops," Nuland said of the code of conduct.

On Clinton's last visit to Asia in July, Southeast Asian nations meeting in Cambodia failed to overcome divisions to move ahead on a code of conduct, with the Philippines and Vietnam seeking the toughest line over disputes with China.

In between her talks in Beijing, Clinton will stop in Indonesia and Brunei, two countries which Chinese Foreign Minister Yang Jiechi toured earlier in August.

President Barack Obama's administration on taking office eyed Indonesia as a growing US partner due to its size, democratic values and mostly moderate practice of Islam, although momentum for stronger ties has since slowed down.

Nuland said that Clinton would also seek a peaceful resolution of disputes involving Japan, whose relations with China and South Korea have rapidly deteriorated in recent weeks.

Clinton will leave on Thursday for the tiny Cook Islands to take part in the Pacific Islands Forum, leading the highest-level US delegation ever to go to the 41-year-old summit.

China has devoted growing attention to the South Pacific, offering assistance with few strings attached in contrast to the region's traditional donors Australia, Japan, New Zealand and the United States.

Clinton, already the most-traveled secretary of state in US history, will on September 6 become the most senior US official ever to visit East Timor, an impoverished half-island which became independent from Indonesia in 2002.

The top US diplomat will end her tour by taking part in the September 8-9 summit of the Asia-Pacific Economic Cooperation forum in the Russian port of Vladivostok.

She will represent the United States instead of President Barack Obama, who has told Russia that he will skip the summit to focus on the home stretch of his re-election bid.

Clinton -- who narrowly lost the Democratic nomination for president to Obama in 2008 -- will miss the party's convention in Charlotte, North Carolina for the Asia trip.

In Vladivostok, Clinton is expected to meet with Russian Foreign Minister Sergei Lavrov. Russia is the main supporter of Syrian President Bashar al-Assad and has butted heads with the United States over the raging fighting in the Arab country.