(CNN) Philippines President Rodrigo Duterte has called for the Chinese government to tone down its behavior in the South China Sea, warning ongoing tensions could spark an accidental conflict.

Speaking Tuesday at the Malacanang Palace in Manila, Duterte said the heavily-contested region could become a "flashpoint."

"I hope that China would temper at least its behavior. I do not want to quarrel with China," he added.

The Philippines and China have been engaged in territorial disputes over parts of the South China Sea for decades, along with Vietnam, Taiwan, Malaysia and Brunei.

Beijing claims an enormous swathe of territory in the region, and has heavily-fortified artificial islands under its control in the Spratly and Paracel chains.