In this file photo, ships of the Japan Maritime Self-Defense Force and U.S. Navy steam together during GUAMEX in 2014. (U.S. Navy/CTR3 Raul Sanchez)

YOKOSUKA, Japan - Guam Exercise (GUAMEX), an annual bilateral training exercise between the U.S. Navy and Japan Maritime Self-Defense Force (JMSDF), began Jan. 20 off the coast of Guam.

Destroyer Squadron (DESRON) 15 guided-missile destroyers USS Mustin (DDG 89) and USS McCampbell (DDG 85) will practice tactical operations along with more than six ships from the JMSDF in a number of exercises including, an anti-air warfare exercise, anti-submarine warfare exercise, and anti-surface warfare exercise.

Maritime assets from the U.S. Navy and JMDSF will include ships, MH-60R Sea Hawk helicopters embarked on Mustin and McCampbell, Maritime Patrol and Reconnaissance Aircraft (MPRA), EA-18G Growlers, and a submarine.

"Our relationship with Japan is grounded in at-sea operations that we conduct with the JMSDF throughout the region," said Cmdr. Ed Sundberg, commanding officer of McCampbell. "It is critical that we learn from each other, so we can continue to improve each country's tactical expertise and response."

Exercises like GUAMEX provide a training environment for enhancing mutual understanding of each country's tactics, communication protocols, procedures and general cooperation. Bilateral operations strengthen U.S.-Japan interoperability and defense capabilities.

Mustin and McCampbell are forward deployed to Yokosuka, Japan and are operating together as part of a planned patrol to promote peace and maritime security in the Indo-Asia-Pacific.