MANILA, May 7 (Xinhua) -- Troops from the Philippines and the United States kicked off on Monday a series of joint military exercises designed to hone their interoperability skills in fighting terrorism and humanitarian assistance.

Philippine Defense Secretary Delfin Lorenzana said the 12-day "Balikatan 2018" will focus on interoperability training to address traditional and non-traditional security concerns.

About 5,000 marines, sailors and airmen from the Philippines, and 3,000 American troops are participating in this year's drills that will be conducted in several locations in the Philippine main Luzon island, authorities said.

U.S. Ambassador to the Philippines Sung Kim said the drills "will not only focus on humanitarian assistance and disaster relief...but also will incorporate training identified in the post-Marawi action reports such as military operation in urban terrain."

A statement issued by the Armed Forces of the Philippines (AFP) said this year's exercises include "a fictional scenario, which will improve the planner's ability to command and control forces from a headquarters level."

The annual "Balikatan" (or Shoulder-to-Shoulder) drills is the most comprehensive among several annual or regular U.S.-Philippines joint military exercises.