Japan, the Philippines and the United States plan to set up a trilateral framework involving their national security advisers, officials familiar with the matter said recently, amid China's growing military assertiveness in the Indo-Pacific region.

Their first discussions under the new plan may take place as early as April, said Eduardo Ano, security adviser to Philippine President Ferdinand Marcos Jr.

Ano said he is "willing to attend" the meeting although details, including which country will host the talks, remain fluid.