South Korea and the United States have agreed to deepen cooperation on key alliance issues, including Seoul's bid to reclaim wartime operational control (OPCON) from Washington and joint efforts to modernise their defence partnership. The commitments were formalised during talks at the Pentagon on Monday between South Korean Defence Minister Ahn Gyu-back and US Defence Secretary Pete Hegseth.

What the Joint Readout Said

"Both the secretary and the minister agreed to remain in close contact and further cooperation in areas of mutual security interest," according to a joint readout released by the Pentagon. The statement added that the two leaders "discussed key alliance issues, including wartime operational control transition and alliance modernisation, and resolved to strengthen cooperation moving forward."

The two sides also reaffirmed the role of the Korea-US Integrated Defense Dialogue (KIDD) — a key bilateral consultation platform — in advancing "alliance cooperation and both countries' national interests." The biennial KIDD meeting is scheduled to take place in Washington on Wednesday and Thursday.

The OPCON Timeline Dispute

The talks come amid apparent differences over the timeline for the OPCON transfer. US Forces Korea commander Gen. Xavier Brunson told Congress last month that the allies aim to meet the conditions for the transfer by no later than the first quarter of 2029. Seoul, however, is reportedly targeting 2028 — while both presidents are still in office — suggesting the two sides may not be fully aligned on the transition schedule.

The Trump administration has stressed increased burden-sharing for allies and called on Seoul to take primary responsibility for deterring North Korea, with what it described as "critical but more limited" US support. Minister Ahn highlighted South Korea's latest efforts to "increase its defense spending, secure critical national defense capabilities and lead the defense of the Korean Peninsula."

Alliance Modernisation and Nuclear Submarines

Secretary Hegseth "underscored the importance of modernizing the alliance while adopting a clear-eyed and pragmatic approach to deter threats and enhance the combined US-ROK defense posture." The two sides likely also discussed Seoul's push to build nuclear-powered submarines — a move that has seen little progress since President Donald Trump gave the green light during his summit with South Korean President Lee Jae Myung in October last year.

Strait of Hormuz Attack Adds New Pressure

The bilateral talks took on added urgency after Seoul announced on Sunday that a recent explosion and fire aboard a Korean-operated cargo ship in the Strait of Hormuz were caused by a strike from two unidentified flying objects. The suspected attack has raised the possibility that Seoul may reconsider its cautious posture in the Middle East and align more closely with US efforts in the strategic waterway.

At the start of the talks, Hegseth called on South Korea and other allies to stand with the US. "The US is looking to South Korea — and all partners and allies — to stand shoulder to shoulder with this country during times of conflict," he said, according to a Pentagon post. Cheong Wa Dae on Monday "strongly" condemned the attack on the cargo ship, pledging to continue joining international efforts to ensure the safe passage of all vessels, including Korean ships. Notably, the joint readout did not include any mention of the Strait of Hormuz or related US initiatives.

What Comes Next

Minister Ahn is on a five-day visit to the US, during which he also plans to meet the acting secretary of the US Navy and members of the US Senate Armed Services Committee. The outcome of the KIDD sessions this week will be closely watched as a barometer of how much ground the two allies can close on the OPCON timeline and burden-sharing expectations.