U.S. Secretary of State Hillary Clinton is in Brunei, becoming the first top U.S. diplomat to visit all 10 members of the Association of Southeast Asian Nations (ASEAN).

Clinton is on a six-nation tour of the Asia-Pacific that has largely focused on urging the ASEAN regional bloc to present a unified front in managing territorial disputes with China.

Brunei is a claimant in the strategic South China Sea, an energy rich area that has become a flashpoint for escalating maritime disputes this year between China and its neighbors. Brunei is slated to become chair of ASEAN next year.

During talks with Clinton in Beijing earlier this week, Chinese leaders rejected U.S. pressure to agree with ASEAN on a code of conduct for managing the disputes in the South China Sea. Beijing prefers to deal individually with rival claimants, which also include Taiwan, the Philippines, Vietnam, and Malaysia.

On Friday, Clinton will head to Russia for a meeting of Asia-Pacific leaders.

Earlier Thursday, Clinton made a brief stop in East Timor, where she said her visit was a “clear, unmistakable sign” that the U.S. will remain a Pacific power.

Following meetings with Timorese officials, she praised Asia's newest country, which gained independence from Indonesia only a decade ago, for holding fair elections earlier this year. She said democracy could help it achieve further stability.

East Timor has received a growing amount of Chinese aid and investment, as Beijing seeks to expand its influence in the region. But Clinton insisted that her visit and increased U.S. involvement is not aimed at curbing Chinese power.