Navies of the four member nations of the Quadrilateral Security Dialogue, or the Quad (India, the United States, Japan, and Australia) are participating in the 25th edition of the Malabar Exercise.
This began off the coast of Guam in the Pacific Ocean.
Malabar began as a bilateral naval exercise between India and the U.S. in 1992.
It was expanded into a trilateral format with the inclusion of Japan in 2015.