U.S. Secretary of State Mike Pompeo is presented with flowers as he boards his plane to depart for Australia from Don Mueang International Airport, in Bangkok, Thailand, Saturday, Aug. 3, 2019. (Jonathan Ernst/Pool Photo via AP)

BANGKOK (AP) — U.S. Secretary of State Mike Pompeo left Thailand on Saturday with his hopes for resuming nuclear talks with North Korea dashed, while facing an escalating trade war with China and a potentially devastating breakdown in relations between key American allies Japan and South Korea.

After three days in Bangkok that the Trump administration had expected could herald an end to the impasse in North Korea negotiations, Pompeo instead departed without progress on that front as Pyongyang continued to launch ballistic missiles, heightening unease over prospects for a denuclearization deal. Pompeo expressed disappointment that the North had sent neither its foreign minister nor a counterpart for the chief U.S. negotiator to the Thai capital.

"I always look forward to a chance to talk with him," Pompeo said on Friday after it became clear he would not be seeing the North Koreans. "I wish they'd have come here. I think it would have given us an opportunity to have another set of conversations, and I hope it won't be too long before I have a chance to do that."

Yet despite what he and other U.S. officials say are ongoing lower-level contacts with Pyongyang, there is no date or venue set for a resumption in negotiations more than a month after President Donald Trump and North Korean leader Kim Jung Un met at the De-Militarized Zone separating the two Koreas. At that time, administration officials said they believed a new round of talks was just weeks away.

Four senior U.S. officials accompanying Pompeo to the annual Association of Southeast Asian Nations regional security forum said North Korea's decision not to attend the conference, which has in the past served as venue for high-level engagement between the two countries, had been a surprise to both the Thai hosts and the other participants. One of those officials said the North's absence was mentioned by every delegation that Pompeo and top U.S. envoy Stephen Biegun met with in Bangkok.

"Unfortunately, the North Koreans missed this opportunity," said the official, who like the others was not authorized to discuss the closed-door discussions publicly and spoke on condition of anonymity. The official added that the North's absence "probably hurts their own interests" and that its failure thus far to agree to a new round of negotiations "is not a positive or constructive response by them."

Although Trump himself has downplayed the missile launches, this official said the recent tests — two of which took place during the ASEAN meeting — were unhelpful provocations that had been a "huge mistake" that caused "self-inflicted damage on their own part." The official said that assessment was widely shared by U.S. partners and that the missile tests may have had the unintended consequence of galvanizing sentiment against the North.

Any convergence of opinion on the North may be one of the few positives to emerge on what had been a full and ambitious agenda for Pompeo in Bangkok.

As he arrived on Wednesday, trade talks between the U.S. and China concluded without result in Shanghai, and Trump then announced new tariffs on Chinese imports in a move that angered Beijing shortly after Pompeo met with China's foreign minister. Then on Friday, Japan downgraded South Korea's trade status, prompting a stern response from the South and escalatory steps by both sides that could jeopardize U.S. interests in both allied countries and more broadly in the Asia-Pacific.

As the situation between Seoul and Tokyo deteriorated on Friday, Pompeo hosted his Japanese and South Korean counterparts at an uncomfortable trilateral meeting on the sidelines of the ASEAN conference. Two senior U.S. officials involved in that discussion acknowledged the seriousness of the dispute but said it was encouraging that the meeting took place at all given the developments.

One of the two officials said the dispute would not affect cooperation on North Korea, while the other expressed hope that tensions could be eased without significant U.S. involvement. The second official said there is "no upside to getting in the middle of this" and suggested that a series of unspecified de-escalatory steps could be taken by each country to prevent the dispute from spiraling.

U.S. Secretary of State Mike Pompeo, second from right, and his wife Susan, right, are greeted by U.S. Ambassador to Australia Arthur Culvahouse and U.S. Consul General Sharon Hudson-Dean as they arrive aboard his plane in Sydney Saturday, Aug. 3, 2019. (Jonathan Ernst/Pool Photo via AP)
U.S. Secretary of State Mike Pompeo waits to exit his plane upon landing at Sydney Airport in Sydney Saturday, Aug. 3, 2019. (Jonathan Ernst/Pool Photo via AP)