MANILA –

China's aggressiveness in the Indo-Pacific is rooted in long-standing strategic ambitions independent of any U.S. policy, and the region's challenges stem from Beijing's own expansionist agenda, the Philippines' top defense official said on Wednesday.

The Philippines and China have had a series of run-ins and heated exchanges in the busy waterway of the South China Sea over the past two years, including an incident in June last year when a Philippine sailor lost a finger.

"The aggressiveness of China has been several years in the making," Defense Secretary Gilberto Teodoro said in an interview at the Reuters NEXT Asia summit in Singapore.