U.S. Secretary of Defense James Mattis on Monday said the country “must be ready” to face threats from North Korea.

Speaking at the Association of the U.S. Army’s annual meeting in Washington, Mattis warned that he could not say what the future holds for the DPRK.

“There’s one thing the U.S. Army can do, and that is you have got to be ready to ensure that we have military options that our president can employ if needed,” the Secretary of Defense said during the keynote speech.

Mattis added that Washington’s current strategy is a “diplomatically led, economic sanctioned, buttressed effort