SEOUL, South Korea — South Korea’s president-elect, Yoon Suk Yeol, said Thursday he would solidify an alliance with the United States, build up a powerful military and sternly cope with North Korean provocations, hours after he won the country’s hard-fought election to become its next leader.

Yoon, whose single five-year term is to begin in May, said during his campaigning he would make a boosted alliance with the United States the center of his foreign policy. He’s accused outgoing liberal President Moon Jae-in of tilting toward Pyongyang and Beijing and away from Washington.

He’s also stressed the need to recognize the strategic importance of repairing ties with Tokyo despite recent bilateral historical disputes.

Some experts say a Yoon government will likely be able to reinforce ties with Washington and improve relations with Tokyo but can’t really avoid frictions with Pyongyang and Beijing.

“I’ll rebuild the South Korea-U.S. alliance. I’ll [make] it a strategic comprehensive alliance while sharing key values like a liberal democracy, a market economy and human rights,” Yoon told a televised news conference.

“I’ll establish a strong military capacity to deter any provocation completely,” Yoon said. “I’ll firmly deal with illicit, unreasonable behavior by North Korea in a principled manner, though I’ll always leave [the] door for South-North talks open.”

After his election win, he spoke with U.S. President Joe Biden on the phone. According to a White House statement, Biden congratulated Yoon on the election and emphasized the U.S. commitment to the defense of South Korea. The statement said the two also committed to maintain close coordination on addressing the threats posed by North Korea’s nuclear and missile programs.

North Korea hasn’t commented on Yoon’s election. In recent weeks, it’s launched a spate of sophisticated, nuclear-capable ballistic missiles in what experts call an attempt to modernize its weapons arsenal and to pressure the Biden administration to make concessions, like sanctions relief, amid stalled diplomacy.

Last week, North Korea said it tested cameras and other systems needed to operate a spy satellite. Its state media on Thursday cited leader Kim Jong Un as saying his country needs reconnaissance satellites to monitor “the aggression troops of the U.S. imperialism and its vassal forces.”

On Japan, Yoon said that Seoul and Tokyo should focus on building future-oriented ties. “The focus in South Korea-Japan relations should be finding future paths that would benefit the people of both countries,” he said.

The two countries are both key U.S. allies and closely linked to each other economically and culturally, but their relations sank to post-war lows during Moon’s presidency over disputes related to Japan’s 1910-1945 colonization of the Korean Peninsula.

Japanese Prime Minister Fumio Kishida on Thursday expressed a desire to communicate with Yoon to bring back good ties. But he still said Tokyo will stick to its position that all compensation issues have been settled by a 1965 bilateral treaty.

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