The United States has vowed to continue the alliance with South Korea to tackle threats from North Korea, after Moon Jae-in, a liberal human rights lawyer and the son of a refugee from North Korea, declared victory in the South Korean presidential election Tuesday.
But experts told VOA that Moon's victory could lessen South Korean resolve to confront North Korea over its nuclear and missile programs, which is a concern among American leaders.
In a statement, the White House said it looked "forward to working with President-elect Moon to continue to strengthen the alliance between the United States and the Republic of Korea and to deepen the enduring friendship and partnership between our two countries."
White House spokesman Sean Spicer said President Donald Trump "looks forward to meeting" with Moon and "talking about our shared interests."
"In working with allies, partners and others" and using "all means at our disposal," Deputy Secretary of State nominee John Sullivan told American lawmakers Tuesday that "our goal is to have a denuclearized Korean Peninsula."
In the nomination hearing, Sullivan told the Senate Foreign Relations Committee that all options are on the table, including "other means at our disposal with the Defense Department," a position reflecting Secretary of State Rex Tillerson's view on North Korea.
A departure from former President Park Geun-hye's hawkish stand against Pyongyang's nuclear and missile provocation, Moon favors greater dialogue with North Korea.
Moon also has been critical of the U.S. deployment of the Terminal High Altitude Area Defense (THAAD) anti-missile system in South Korea, arguing that Washington should have waited for a new president to make the final decision to install it.
Moon had traded words with Trump over who should pay for deployment of the $1 billion system.
"There will almost certainly be tensions and rifts with the U.S. over North Korea," Atlantic Council senior fellow Robert Manning told VOA.
"If Moon reopens the Kaesong industrial zone unconditionally, undermining sanctions and providing hard currency to Pyongyang, that would be a source of contention," he added.
No 'Sunshine' revival seen
Manning said that while Moon was likely to take some steps toward dialogue with North Korea, he was unlikely to revive fully the "Sunshine Policy," a policy of engaging with Pyongyang initiated in the early 2000s, because North Korea's aggressive missile and nuclear tests would "curb his enthusiasm."
Former senior U.S. officials cautioned Seoul to maintain a "united stance" with Washington.
"I would hope that President Moon will take the time to have in-depth discussions with the United States before making any decisions on reopening a dialogue with North Korea," Dennis Wilder, a former senior director for East Asian affairs at the National Security Council under President George W. Bush, told VOA.
In a statement, Representative Eliot Engel, a New York Democrat who is the ranking member of the House Foreign Affairs Committee, called on Seoul's new government to work with Washington "to leverage the strength of our alliance and maintain close cooperation" to address the growing threat posed by North Korea.
While the government change in Seoul may have introduced a level of volatility, some argue it will not change the U.S.-South Korea-Japan alliance significantly.
"Washington and Tokyo can make the most of it by keeping in close coordination with Moon's team to create a 'good cop, bad cop' dynamic," said James Schoff from the Carnegie Endowment for International Peace.
Schoff added "the key for Washington and Seoul is to make sure they coordinate closely" so that Pyongyang or Beijing cannot exploit the division between them.
Jonathan Pollack, a senior fellow at the Brookings Institution, told VOA that while generally there is strong support from South Korea to maintain the alliance with the U.S., Seoul does not like to be instructed by Washington about what to do and what not to do.
"It underscores the importance of an early face-to-face meeting" between Trump and Moon, Pollack told VOA in a teleconference.
Pollack said tweets from a president are "not the way to explain policy" among the leadership circle, and if there's already damage caused to bilateral relations, a face-to-face meeting can keep the damage at "a minimal level."