(Bloomberg) —Donald Trump will spend 10 days touring Asia on his first visit as U.S. president, traveling to five countries and attending several summits. One man he won’t see could loom largest over his trip.

North Korean leader Kim Jong Un’s accelerated missile and nuclear weapons program has made him one of the biggest geopolitical threats to the U.S. administration. Kim’s antics have taken up a chunk of Trump’s time this year, with each warning the other of potential annihilation and bringing tensions in North Asia to their highest in decades.

North Korea on Thursday accused the U.S. of “seeking to ignite a nuclear war” while saying American fighter jets staged a drill in South Korea that replicated a surprise nuclear attack on Kim’s regime. Two B-1B strategic bombers conducted bilateral missions with Japanese and South Korean fighter jets in a previously scheduled operation, U.S. Pacific Air Forces said.

Yet beyond the drills and rhetoric, there’s little sense of a way forward before Trump travels to Japan, South Korea and China, and attends a meeting of Asia-Pacific leaders in Vietnam where North Korea is expected to dominate the agenda. As Trump’s team struggles to articulate a unified policy on dealing with Pyongyang, leaders in Asia are seeking clarity.

“We do not know whether there is unity of opinion within the administration,” said Fumiaki Kubo, a professor of American government at the University of Tokyo. “Unpredictability has a certain value. It makes the enemy nervous, but it also makes allies nervous.”

Trump has said the time for talking is over. Japan’s Prime Minister Shinzo Abe agrees talks are a waste of time and wants a combination of sanctions and military deterrence. China, South Korea and Russia have favored a diplomatic approach, even as they supported recent sanctions. Russia’s President Vladimir Putin has said that sanctions don’t work.

Added to the mix is Trump’s periodic public frustration with Beijing for what he says is a lack of action to rein in North Korea as its main ally and biggest trading partner.

The Asia-Pacific Economic Cooperation summit next week in Danang, Vietnam, is the first chance in months for Trump, Abe, Putin and the leaders of China and South Korea to talk directly about the matter.

The stakes are high. Some Asian leaders have called on all sides — the U.S. included — to tone down the rhetoric out of concern that Pyongyang and Washington are careering toward a conflict that could  devastate the Korean peninsula. At the same time, the U.S. has said it can’t allow Kim to be able to hit its mainland with a nuclear warhead.

One of Trump’s priorities will be to bring South Korea and Japan into closer alignment with each other and the U.S., according to a White House official who asked not to be identified discussing the president’s approach to the matter. The U.S. would like its allies to better coordinate their sanctions regimes, and bring their penalties in line with those implemented by the Trump administration, the official said.

Japan is seeking further pressure on Pyongyang, and wants assurances Trump will stick to this approach, according to a diplomat who asked not to be identified speaking about policy. That means squeezing Kim in order to get him to change his behavior, the diplomat said.

The White House also wants to improve the trilateral relationship with Seoul and Tokyo, according to the U.S. official. Japan’s colonization of the Korean peninsula decades ago still bedevils ties. The goals are both concrete — joint military exercises — and symbolic, with the U.S. encouraging the countries to demonstrate trust in one another.

Seoul Tensions

Trump will meet families of Japanese citizens who were abducted by Pyongyang. He doesn’t plan to visit the the Demilitarized Zone between the two Koreas.

In contrast to the warm ties between Trump and Abe, there have been tensions with South Korean President Moon Jae-in. They surfaced in August, when Moon asserted a right to veto any U.S. strike against North Korea, with Trump later accusing Moon of “appeasement.” South Koreans are wary of Trump’s alleged comments to Senator Lindsey Graham that “if thousands die, they’re going to die over there.”

Moon’s administration will view Trump’s visit as a success if he reaffirms his commitment to defend South Korea and says tensions with Pyongyang should be resolved peacefully, according to a government official with knowledge of the discussions.

Defense Secretary Jim Mattis agreed in late October to expand U.S. strategic assets on the Korean peninsula. The Navy has three aircraft carriers and their assorted missile-carrying vessels operating in or deploying to the western Pacific Ocean for the first time since 2011.

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The U.S. is also hoping to get China to maximize pressure on North Korea, the White House official said. A second senior administration official, who requested anonymity, said the U.S. would seek further unspecified steps from China in addition to full implementation of United Nations Security Council resolutions.

“I believe he’s got the power to do something very significant with respect to North Korea,” Trump said of Xi in a late October interview with Fox Business. “We’ll see what happens.”

Still, Trump may be disappointed. “China has been doing everything we can on the Korean issue,” Ambassador  Cui Tiankai told reporters in Washington on Monday. China has proposed the U.S. and North Korea both make concessions to return to talks, but that’s been rejected by the Trump administration.

Xi notably called for stable China-North Korea ties in a message to Kim just days before Trump’s arrival, responding to a congratulatory message last week from the North Korean leader on Xi’s second term as Chinese leader. The countries should make a “positive contribution” to defending regional stability, Xi said.

Trump’s personality adds another dimension to the trip, according to Zhang Baohui, director of Lingnan University’s Centre for Asian Pacific Studies in Hong Kong.

“Trump’s ego dictates that he cannot be seen to be beaten by someone else, this is why he and Kim have been engaging in a war of words, with the prospect of a real war looming,” Zhang said. “So he is unlikely to be persuaded by Xi to engage Kim through diplomacy. Nothing short of total victory, which means North Korea giving up its nuclear weapons, will satisfy him.”