MANILA, Sept 28 (Reuters) - Australia and the Philippines said their militaries would conduct a joint maritime activity with Japan, New Zealand and the United States in the exclusive economic zone of the Philippines, which covers one of Asia's most sensitive sites.

"The Maritime Cooperative Activity demonstrates our collective commitment to strengthen regional and international cooperation in support of a peaceful, stable and prosperous Indo-Pacific," Australia's Department of Defence said in a statement on Saturday.

Navy ship HMAS Sydney and a Royal Australian Air Force P-8A Poseidon maritime patrol aircraft will operate with the partner nations to boost "cooperation and interoperability between our armed forces", the statement added.

The joint exercise comes after a series of air and sea encounters between the Philippines and China, which have sparred over disputed areas of the South China Sea, including the Scarborough Shoal, one of Asia's most contested features, which has been occupied by China's coast guard for more than a decade.

On Wednesday, naval vessels from New Zealand and Australia sailed through the Taiwan Strait, part of the South China Sea, a move Australia's Department of Defence said showed the country's commitment to an open, stable and prosperous Indo-Pacific.

China, which claims democratically governed Taiwan as its own, says it alone exercises sovereignty and jurisdiction over the strait. Both the U.S. and Taiwan say the strait - a major trade route through which about half of global container ships pass - is an international waterway.

Australia has "consistently pressed China on peace and stability in the South China Sea and Taiwan Strait", Australia's Foreign Minister Penny Wong said in a speech to the United Nations General Assembly on Saturday.

"We have welcomed the resumption of leader and military level dialogue between the U.S. and China," Wong said, according to a transcript.

China claims nearly all of the South China Sea, despite overlapping maritime claims by Brunei, Malaysia, the Philippines and Vietnam, angering its neighbours.

Photo from AP