China says its navy will soon begin training exercises in the western Pacific, in a move that could add to unease among some of its neighbors.

The drill comes amid China's increasingly assertive maritime claims in the South and East China Seas, and just a week after U.S. President Barack Obama announced plans to station U.S. marines in northern Australia.

In a statement late Wednesday, China's defense ministry said the exercise will begin before the end of this month. It said the drill will adhere to relevant international laws and practice and is not directed against any particular country.

The statement also said China's lawful rights, including free navigation in relevant waters, should not be hindered.

China has been building up its naval power, including a sea trial this year of its first aircraft carrier. The build-up has been accompanied by a major diplomatic dispute with Japan over islands in the East China Sea and moves to disrupt oil and gas exploration by Vietnam and the Philippines in disputed areas of the South China Sea.

Mr. Obama's decision to station U.S. troops in Australia was widely interpreted as a move to balance China's rising power. During his high-profile visit to the region last week, Mr. Obama announced a policy “pivot” toward Asia and declared the United States is in Asia to stay.