HONG KONG (AP) - A U.S. Navy admiral expressed new concern Friday over China’s military buildup and urged Beijing to be clearer about its intentions.

With China’s military growing at an "unprecedented rate" - spending was up almost 15 percent in the 2009 budget - the U.S. wants to ensure that expansion doesn’t destabilize the region, Rear Adm. Kevin Donegan told reporters on a visit to the Chinese territory of Hong Kong.

"When we see a military growing at that rate, we’re interested in transparency and the understanding of the uses of that military," said Donegan, commander of the USS George Washington aircraft carrier strike group, a key part of the U.S. Pacific Fleet.

Donegan’s comments come as a top Chinese general visits the United States on a mission to strengthen trust between the two militaries and dispel U.S. concerns about the growth of the People’s Liberation Army.

Xu Caihou, the PLA’s second-highest ranking officer, told President Barack Obama on Wednesday that ties between the two countries’ militaries play "an important role in enhancing strategic mutual trust and deepening their pragmatic cooperation," according to Chinese media reports.

Donegan’s remarks echo the concerns of other U.S. military leaders who say fast growth in China’s military spending raises questions as to how Beijing plans on deploying its new power.

China has boosted spending by more than 10 percent annually for almost two decades, and the official figure of $71 billion this year is thought by many analysts to represent only a portion of total defense spending. It still amounts to only a fraction of U.S. defense spending.