In an undated statement, the ministry cited an "increasingly severe security environment surrounding Japan," noting that "it is critical to enhance ISR [intelligence, surveillance and reconnaissance] activities by both countries," adding that the drones "will be temporarily deployed to Japan after mid-May."

"This deployment is intended to demonstrate U.S. commitment to Japan's Defense and will be beneficial to security of Japan by strengthening the ability of maritime surveillance around Japan, given the increasingly active maritime activities by surrounding countries," the ministry said.

It is the first time that Triton unmanned aerial vehicles will be temporarily deployed to Japan, Stars & Stripes reported.

The two Tritons were scheduled to arrive at Naval Air Facility Misawa, Japan, where the United States has naval aviation operations, this weekend, USNI reported.

The drone is a maritime surveillance version of the Global Hawk, and is regularly deployed from Guam to Japan by U.S. forces since 2014.

Adm. Jim Kilby told House Armed Services subcommittees in March that the presence of Triton drones in the Pacific Ocean area "allows us to create a more complete picture of what is out there versus what we think is out there."

"So I think Triton will add tremendous value there," Kilby said.