America’s relationship with North Korea remains a diplomatic one, Secretary of Defense Jim Mattis said Monday, but he urged members of the military to be prepared in case the situation breaks down.

Mattis also used his keynote speech at the annual AUSA conference in Washington, D.C., to thank allies who have stood with the U.S. through the ages.

Mattis tells troops their job is to 'be ready' during North Korea diplomatic push Secretary of Defense Jim Mattis tells troops their job during diplomatic efforts with North Korea is to 'be ready' to provide a military option, during a speech at the Association of the United States Army's annual conference on Oct. 9, 2017, in Washington, D.C.

“It is right now a diplomatically, economic-sanctions-buttressed effort to try and turn North Korea off of this path,” Mattis told the audience. “What does the future hold? Neither you nor I can say.”

Tensions with North Korea have ratcheted up since the start of the year, following a series of missile launches that culminated in a nuclear test on Sept. 3. Those tensions have been matched with rhetoric from President Donald Trump, who regularly issues provocative tweets and has taken to calling North Korean leader Kim Jong-Un “rocket man.”

Click here for more coverage from the AUSA 2017 conference.

There is a belief among experts that North Korea will attempt some kind of launch or detonation late Monday, timed around a local holiday. As of publication, weather reports show non-ideal conditions for a launch, which may delay whatever show of force is being considered from Pyongyang.

In contrast to some of the president’s tweets, Mattis’ comments represent a fairly regular baseline of the North Korea situation — that diplomacy has the lead, with the military ready to back it up.

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Presidents and their administrations have been talking to North Korea for 25 years, agreements made and massive amounts of money paid...... — Donald J. Trump (@realDonaldTrump) October 7, 2017

...hasn't worked, agreements violated before the ink was dry, makings fools of U.S. negotiators. Sorry, but only one thing will work! — Donald J. Trump (@realDonaldTrump) October 7, 2017

“There is one thing the U.S. Army can do, and that is you have to be ready to ensure we have military options that our president can deploy if needed,” Mattis said. “The international community has spoken, but that means the U.S. Army must stand ready. “

“So if you’re ready, that’s your duty at this point and time, and I know the Army will always do its duty.”

Readiness for a major conflict was a theme throughout the secretary’s speech, which burrowed into the Army’s history and came with a series of book recommendations. The big takeaway, Mattis emphasized, was that the Army needs to be ready to go at a moment’s notice because if diplomacy fails, the military must be deployable right away.

“What we want to do is be so ready and be very much aware that we fight the way we come, that everybody in the world wants to deal with Secretary Tillerson and the Department of State, not the Department of Defense and the United States Army,” Mattis told the audience to applause.

Diplomacy, and allies, were also a theme of the speech, with Mattis noting that while he has “had the honor of fighting many times for America,” he never fought in a purely American force structure.

“From NATO to Europe to the Pacific, our message to our allies is ‘we are with you,’” Mattis said.