BRUSSELS — NATO defense chiefs have committed to keeping the Western alliance "ready, relevant and able."

The pledge came at a meeting of the Military Committee, NATO's highest military authority, on Thursday at the NATO headquarters in Brussels, Belgium.

The meeting, which discussed NATO operations and missions, comes a few days ahead of a much-awaited visit to the Middle East and Europe by U.S. President Donald Trump, his first overseas trip as commander in chief. This includes attending the meeting of NATO leaders in Brussels on May 25.

Trump in the past has called NATO "obsolete" — comments he has since partially withdrawn — and called on alliance members to "pay their fair share" toward the cost of Europe's defense. In 2014, NATO members committed to spending 2 percent of GDP on defense, but only a handful, including the United States, have so far met that target. 

Throughout the day's discussions, NATO defense chiefs stressed their commitment to keeping the alliance "ready, relevant and able, while also addressing the potential for joining the global coalition against the Islamic State group and enhancing NATO's contribution to fighting terrorism.

The defense chiefs also spoke of the need to have a "consistent, coordinated and coherent" approach that "enables NATO to provide more assistance" to the alliance's partners.

Speaking at a news conference at the NATO headquarters, U.S. Gen. Curtis Scaparrotti, supreme allied commander Europe of NATO Allied Command Operations, said the alliance "must do more to ensure a Europe that is whole, free and at peace."

NATO's supreme allied commander Europe, Gen. Curtis Scaparrotti, left, waits for the start of a meeting of NATO chiefs of defense at NATO headquarters in Brussels on May 17, 2017.

Photo Credit: Virginia Mayo/AP

Describing the one-day meeting as "profitable," he praised the "contributions from across the alliance to NATO operations and to the defense of Europe."

"I also appreciate how difficult it is in these complex times to meet all the requirements in the light of high demand and continued resource constraints to provide all the forces that we require," he told reporters.

Even so, further effort by NATO members was needed, he added, including "a change in our posture, in our mindset and our ability to respond at the speed of conflict."

"Clearly, NATO is changing; we are adapting the alliance to respond to different approaches to modern warfare, which is extremely complex, potentially vast in scale, scope and intensity. And we continue to work as allies to succeed in this significant transition," he said.

National, bilateral, and collective alliance efforts were, he said, "fundamental" to NATO's future success. "NATO nations are responding nationally, multilaterally and collectively. Looking forward, we must maintain a strategic, long-term view. We must have a sense of urgency coupled with a sense of endurance.

"NATO is charged to be ready and responsive to the new and continually ... evolving security environment. We must continue to set the conditions and invest now to ensure European stability in the future."

Chairman of NATO's Military Committee Gen. Petr Pavel delivers the opening address during a meeting of NATO chiefs of defense at NATO headquarters in Brussels on May 17, 2017.

Photo Credit: Virginia Mayo/AP

Also speaking at the closing joint news conference, Gen. Petr Pavel, chairman of the Military Committee, said: "What is crucial is that the military advice we provide is clear, concise and, importantly, able to deliver the desired strategic effects."

Pavel is a Czech Army officer and the first person from a former Eastern bloc state to hold the position.

Further reaction to the outcome of the committee, which meets twice a year, came from Gen. Denis Mercier, supreme allied commander transformation of NATO, who said: "Since our last meeting in January, we reached a significant milestone in achieving 100 percent apportionment and acceptance on NATO capability targets by the 28 allies and Montenegro."

Mercier, a former French Air Force chief of staff, added: "These targets are based on the military requirements translated directly from the political guidance, and they are based on the principles of fair burden sharing and reasonable challenge."

Martin Banks covered the European Union, NATO and affairs in Belgium for Defense News.

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