The top U.S. military officer says Washington is committed to maintaining its military presence in Asia, and that the United States and China must work together to ensure regional security.

Admiral Mike Mullen, chairman of the U.S. Joint Chiefs of Staff, made the comment Sunday at the start of a four-day trip to China. The official Xinhua news agency said he met Monday morning with Chen Bingde, chief of staff of the Chinese military.

On Sunday, Mullen said Washington is worried that disputes between China and two of its neighbors could spiral out of control. Beijing is at odds with the Philippines and Vietnam over competing territorial claims in the resource-rich South China Sea.

Later, he told students at Beijing's prestigious Renmin University that the United States is, and will remain, a Pacific power. But he said the regional and global challenges that the U.S. and China face together are too large and too vital to be blocked by misunderstandings between the two sides.

Admiral Mullen also pushed for greater openness from China's growing military. He said that “with greater military power must come greater responsibility, greater cooperation and just as important, greater transparency.”

On Monday, Mullen is also scheduled to meet with Vice President Xi Jinping, Defense Minister Liang Guanglie and other officials. The meetings will focus on stalled nuclear disarmament talks with North Korea, the Taiwan issue and confidence building measures between China and the United States.

Later in the week, Admiral Mullen is due to visit Chinese military bases outside Beijing.

China, the Philippines, Vietnam, Malaysia, Brunei and Taiwan all claim territory in the South China Sea, with most of those claims centered on the potentially energy rich Paracel and Spratly island chains. China's claim is the largest and it has issued sharp warnings in recent weeks, including threats of military action, to enforce its claims.