Patrick Shanahan, acting U.S. Secretary of Defense, in Washington, D.C., on May 21, 2019.

WASHINGTON — Acting Defense Secretary Patrick Shanahan on Friday blamed Russia for the near-collision between U.S. and Russian warships hours before and indicated the militaries of the two countries will discuss the matter.

"There was obviously a safety issue there. That behavior was unsafe and unprofessional. We'll have military-to-military conversations with the Russians," Shanahan told reporters outside the Pentagon.

He said the incident "will not deter us in our operations."