South Korea’s new president Lee Jae-myung brings uncertainty to Seoul’s foreign policy

Left-leaning election winner has previously made controversial foreign policy statements and could move Seoul closer to Beijing, at a time when North Korea poses a growing threat.

Expert comment Published 4 June 2025 Updated 5 June 2025 4 minute READ

Dr Edward Howell

Korea Foundation Fellow, Asia-Pacific Programme

South Korea elected the left-leaning Democratic Party candidate, Lee Jae-myung, as its new president on 3 June. The snap election followed the impeachment of President Yoon Suk Yeol in April, after the conservative leader declared martial law on 3 December last year. 

Lee won the election with 49.42 per cent of the vote, ahead of the People Power Party candidate, Kim Moon-soo, at 41.15 per cent. His victory is not a surprise. In the weeks prior to the election, Lee had commanded a sizeable, albeit tightening, lead over his rivals. At 79.4 per cent, turnout was the highest since 1997, perhaps reflecting the heightened stakes and sharp political divisions within South Korean society. 

The new South Korean president now faces a myriad of domestic, regional, and global challenges, including domestic political polarization, escalating threats from North Korea and China, and evolving dynamics in Seoul’s alliance with Washington. 

Third time (un)lucky

Lee’s victory follows two previous unsuccessful attempts to run for president. In 2017, he failed to win the Democratic Party nomination, while in 2022, he won the party nomination but was narrowly defeated by the conservative Yoon Suk Yoel. His successful third attempt comes at a time of heightened domestic challenges, which the new president and his party will have to address swiftly.

The new Lee government will also have to confront ongoing polarization within South Korean society. 

South Korea faces sluggish domestic economic growth, owing to a toxic combination of declining consumer spending and investment, which pre-date the Trump administration’s imposition of potentially damaging tariffs earlier this year. Only last week, the country’s central bank, the Bank of Korea, reduced interest rates from 2.75 per cent to 2.5 per cent, their lowest level since August 2022. 

The new Lee government will also have to confront ongoing polarization within South Korean society. While this polarization is hardly new, domestic division across and within party lines has become more entrenched following the declaration of martial law by Lee’s predecessor, Yoon Suk Yeol, last year. These divisions show few signs of abating under a new government. 

Lee faces the further challenge of managing the significant personal scandals in which he is mired. After taking office, the new president will face imminent criminal charges, including for allegedly breaking election law during his 2022 presidential election campaign and embezzling public funds. Another charge pertains to the alleged illicit transfer of $8 million to North Korea through a South Korean conglomerate between 2019 and 2020, while Lee was governor of Gyeonggi Province. These criminal hearings are due to take place later in June. 

South Korea at the crossroads

Lee’s victory comes at a precarious juncture for South Korean foreign policy amid escalating local, regional, and global security threats. Ongoing US–China competition, the Trump administration’s sweeping imposition of tariffs, and heightened aggression from China and North Korea, coupled with Seoul’s historically fraught relations with Tokyo, are just some of the challenges the new government will face.

It is still too early to know the precise foreign policy that Lee will pursue. Previous left-leaning administrations in Seoul have adopted conciliatory approaches towards North Korea and China, and so-called ‘equidistant’ foreign policies of hedging between Washington and Beijing. However, before and during the election, Lee attempted to portray his left-leaning party as a ‘centrist-conservative’, though the extent to which this rebranding will shape his foreign policy stance remains unclear. 

Lee’s victory comes at a precarious juncture for South Korean foreign policy.

Lee’s claims in his inauguration speech could be seen as an attempt at this ‘centrist’ rebranding. In his speech, he pledged to ‘reinforce the Korea-US alliance’ and ‘strengthen trilateral cooperation’ between the US, Japan, and South Korea. Although Washington and Tokyo may be reassured by these words, the possibility of South Korea pivoting from the US and towards China cannot be ruled out.

The Trump administration’s as-of-yet ambiguous foreign policy approach towards South Korea might restrain any significant volte-face in South Korean foreign policy, at least in the short-term. Moreover, Washington’s present policy towards North Korea seems to prioritise deterring Beijing over Pyongyang. Any South Korean rapprochement with China risks the potential of straining Seoul-Washington ties.

That said, both Trump and Lee have previously criticized the presence of US troops in South Korea. Lee himself previously described the United States Forces Korea as an ‘occupying force’. Any change in the nature of the US conventional presence on the Korean Peninsula risks undermining a vital cornerstone of regional security with potentially damaging consequences for security on the Peninsula and beyond.  

Past controversies

While Lee’s inauguration speech committed to sustaining relations with the US and Japan, he has previously made highly controversial statements that have alarmed Seoul’s allies and partners, not least in suggesting that he will move Seoul closer to Beijing. During his previous election attempt, in addition to criticizing the US troop deployment in South Korea, Lee came under fire for sympathizing with China’s criticisms of the US-operated Terminal High Altitude Aerial Defence (THAAD) missile-defence system in South Korea. 

Moreover, Lee has demonstrated signs that he might pursue a more China-friendly stance on Taiwan than his predecessor. During a campaign rally in March this year, Lee dismissed relations between China and Taiwan as having ‘nothing to do’ with South Korea, and stressed how South Korea should ‘keep [its] distance from a China-Taiwan contingency’, in the hope of ‘get[ting] along with both’.

He has also previously criticized plans for South Korea to deploy lethal assistance to Ukraine, where an estimated 14,000 North Korean troops are fighting alongside Russian forces. Lee will now need to clarify his position on the war, which posed a point of contention for his conservative predecessor, Yoon Suk Yeol, who refused to supply lethal assistance to assist Ukraine.  

North Korea

Amid these regional and global challenges, South Korea faces a heightened threat from its primary foreign policy challenge, namely, North Korea. Pyongyang has been emboldened by its increasing cooperation with Moscow since the outbreak of Russia’s war against Ukraine in February 2022, which has included the supply of advanced weaponry to North Korea.

In his inauguration speech, Lee mentioned how Seoul would ‘pursue dialogue and cooperation’ with Pyongyang to build ‘peace on the Korean Peninsula’. Prior to his election, Lee also pledged to restore the hotline between North and South Korea, which North Korea severed in 2023. Yet, with North Korea currently showing little intention of engaging in talks with the South, any such efforts may prove to be futile.

At a time when international institutions – not least the UN Security Council – remain unable to constrain both North Korea’s nuclear development and its cooperation with Russia, the new South Korean administration must strengthen existing efforts at deterring North Korea, particularly through continuing military exercises with the US and Japan.

The next few months of transition will therefore be crucial for South Korea and the wider region. It remains to be seen whether Seoul’s foreign policy direction will be one of continuity or change from the previous administration.  

While change is likely, a concerted approach between Washington, Seoul, and Tokyo is crucial in order to address the ever-increasing threats emanating from Moscow, Pyongyang, and Beijing.