South Korean Prime Minister Han Seong-sook met with US Ambassador to South Korea Michelle Steel in Seoul on Wednesday, 23 September 2026, to explore avenues for deepening bilateral cooperation across security, trade, and emerging industries. The high-level meeting signals continued momentum in the South Korea-US alliance at a time when both capitals are working to translate a landmark summit agreement into concrete outcomes.

Key Developments from the Meeting

During the talks, Prime Minister Han noted that the bilateral partnership had grown well beyond its original security foundations to encompass the economy and culture. She specifically urged Ambassador Steel to take an active role in advancing ties during her tenure in Seoul.

Han also expressed hope that the two countries would expand economic cooperation and mutual investment, pointing to shipbuilding, semiconductors, and artificial intelligence as priority sectors for achieving 'greater outcomes.'

Ambassador Steel, who was born in Seoul, responded by pledging efforts to build a 'stronger' alliance across security and investment, describing the partnership as 'blood-forged.' She also highlighted South Korea's remarkable economic ascent and its growing global cultural influence since she left the country decades ago.

Steel's Remarks on X

Following the meeting, Steel posted on X: 'Today, I met with Prime Minister Han Seong Sook and reaffirmed the deep and unwavering ROK-US alliance. I look forward to continued close cooperation in the future for our two countries' shared priorities.' She added: 'Had a great meeting with PM Han Seong Sook today and reaffirmed the deep and enduring US-South Korea Alliance. Looking forward to continued cooperation on shared priorities.'

Foreign Minister Cho's Diplomatic Push at the UN

Separately, South Korean Foreign Minister Cho Hyun met with US Senators Jeanne Shaheen (Democrat, New Hampshire) and Chris Coons (Democrat, Delaware) in New York on Monday while attending the UN General Assembly's high-level week. Discussions covered the South Korea-US alliance, Korean Peninsula issues, and broader regional affairs.

Cho referenced his recent bilateral talks with US Secretary of State Marco Rubio in Washington, during which both sides agreed to maintain close communication for the faithful implementation of summit agreements. He called on the US Congress to actively support swift progress in strategic cooperation, particularly in shipbuilding and nuclear energy.

The Summit Agreement and Its Stakes

The backdrop to these diplomatic engagements is a joint fact sheet issued in November following a summit between South Korean President Lee Jae Myung and US President Donald Trump the previous month. Under that framework, Seoul committed to investing USD 350 billion in the United States — including USD 150 billion earmarked for shipbuilding cooperation — in exchange for lower US tariff rates.

The agreement also covers security arrangements, including Seoul's push to develop nuclear-powered submarines and secure rights to enrich uranium and reprocess spent nuclear fuel — provisions that carry significant strategic weight on the Korean Peninsula.

Senators Shaheen and Coons reaffirmed strong bipartisan congressional support for the alliance and welcomed South Korean investments in the US, noting their contribution to American job creation and manufacturing revival. Both senators pledged continued attention to the smooth implementation of summit agreements and active cooperation toward peace and stability on the Korean Peninsula.

What's Next

With Foreign Minister Cho's UN-sideline diplomacy and Ambassador Steel's fresh pledge of engagement, both governments appear intent on maintaining the alliance's upward trajectory. The practical test will be the pace at which the USD 350 billion investment framework and its nuclear energy and submarine provisions are operationalised in the months ahead.