SINGAPORE — U.S. Defense Secretary Jim Mattis used his address at a regional security summit in Asia to again criticize North Korea’s continued destabilization of the region with its nuclear program, while reassuring nervous allies that the United State will continue to seek to strengthen its alliances and commitment to the region.

In his speech, Mattis also urged China to follow through with action its stated desire to see North Korea denuclearize, but pledged that the United States will "engage China diplomatically and economically to ensure our relationship is beneficial."

Mattis, speaking at the first plenary session of the annual Shangri-La Dialogue in Singapore, also touched on the threat of terrorism to the region, emphasizing the need to "defeat extremist organizations wherever they attempt to establish roots."

As expected, Mattis saved his harshest words for North Korea, calling its nuclear weapons program a threat to all, and taking the Kim Jong-un regime to task for its "long record of murder of diplomats, of kidnapping, killing of sailors, and criminal activity."

Highlighting that "the United States regards the threat from North Korea as a clear and present danger," Mattis also noted that the Pyongyang regime has been increasing the pace and scope of its efforts in the continued pursuit of nuclear weapons and the means to deliver them.

He repeated that the United States will continue working with the United Nations, allies and partners to increase diplomatic and economic pressure "until Pyongyang finally and permanently abandons its nuclear and ballistic missile programs."

These partners include China, with Mattis saying that the Trump administration is encouraged by its "renewed commitment to work with the international community toward de-nuclearization," adding that he believed China will eventually see North Korea as a strategic liability and not an asset given its propensity for inciting disharmony.

Touching on relations with China, Mattis reiterated that the United States seeks a constructive, results-oriented relationship, believing that it can "engage China diplomatically and economically to ensure our relationship is beneficial not only to the United States and China, but also to the region and to the world."

Nevertheless, China was reminded by Mattis that its "artificial island construction and indisputable militarization of facilities on features" in the international waters of the South China undermine regional stability, while also reasserting the U.S. military’s right to "continue to fly, sail and operate wherever international law allows and demonstrate resolve through operational presence in the South China Sea and beyond."

Many of the delegates and participants at the Dialogue, however, were more interested in Mattis’ thoughts on the Trump administration’s approach to the ties and interactions with increasingly nervous regional allies and partners, with Mattis asked at the question and answer session if the American-led global order is in the process of being dismantled.

Mattis responded that "like it or not, we are part of the world." He insisted that the United States will "still be there," noting that the Trump administration will pursue "a fresh approach" while asking for patience from regional allies. "Bear with us, once we have exhausted all possible alternatives, the Americans will do the right thing," Mattis said, paraphrasing a quote often attributed to Winston Churchill.

The general consensus among the delegates who were present at the speech was that Mattis had struck the right notes in reassuring nervous allies, but the proof of the pudding remains the actions taken by the White House. Mattis "did as good a job as could be expected by saying all of the right things on commitment, alliances and capabilities," Euan Graham, director of Australia's Lowy Institute for International Policy's International Security Program, told Defense News. But, the "broader, more searching questions about US engagement in Asia extend beyond the military realm, to include economics in particular," still remain.

Mike Yeo is the Asia correspondent for Defense News.

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