US Defense Secretary Lloyd Austin and NATO Secretary General Jens Stoltenberg met Monday ahead of a NATO summit in Washington, D.C. marking the 75th anniversary of the alliance.
"This summit will celebrate 75 years of the greatest defensive alliance in history," Austin said.
"The summit will deepen our extraordinary transatlantic bond and strengthen our shared security."
His remarks came a day before the summit, where 32 NATO allies will gather to make key decisions on how to continue to protect their one billion citizens as the world faces the "most dangerous" security environment since the Cold War.
The alliance has made "outstanding progress" in strengthening deterrence and defense, Austin said.
Austin awarded Stoltenberg the Defense Department's Medal for Distinguished Public Service, the highest honor that the secretary of defense can present to a non-US citizen.
"At your very first meeting of the North Atlantic Council, you said 'to be strong, NATO must remain ready — ready to take decisions and to adapt as challenges emerge,'" Austin said.
Seventy-five years ago, 12 countries signed the North Atlantic Treaty in Washington, D.C. to ensure their collective defense in an unpredictable world.