Seoul summit: South Korea and Turkey seal nuclear financing and defence pact

Two leaders, four memorandums, one Black Sea reactor

South Korean President Lee Jae Myung and Turkish President Recep Tayyip Erdogan agreed on Tuesday, November 3, 2026, to deepen cooperation in nuclear energy and defence, during a summit at the presidential palace in Seoul. After one-on-one and delegation-level talks, their ministers signed four memorandums of understanding covering energy, nuclear project financing, natural resources and mining, and science and technology; the two countries' investment promotion agencies signed a fifth separately.

Erdogan arrived on Monday for a three-day state visit, his first to South Korea since 2018, and told the Yonhap News Agency beforehand that South Korea could become a partner in Turkey's planned nuclear power plant at Sinop, on the Black Sea coast. On defence, Lee said the two countries would "deepen defence cooperation by expanding joint production and technological cooperation, while also exploring opportunities for companies from both countries to jointly enter third-country markets." Erdogan called defence "one of the primary areas where our strategic partnership has yielded concrete results," citing joint work on Fırtına howitzers and the Altay main battle tank.

The paper trail from Ankara 2025 to Seoul 2026

The Seoul agreements extend a memorandum signed in November 2025, when Lee visited Ankara: South Korea's Korea Electric Power Corp. (KEPCO) and Türkiye Nükleer Enerji A.Ş. agreed to cooperate on Sinop, and have since launched a preliminary feasibility study with site evaluation and a joint working group. On Tuesday, Lee said both sides judged that cooperation "has been progressing smoothly."

The new financing memorandum is the summit's practical core. Signed by Export-Import Bank of Korea president Hwang Ki-yeon and TNA chief executive Necati Yamaç, it provides for project information exchanges, financing feasibility assessments and the identification of funding opportunities to back Korean companies' bid for Sinop. The broader energy memorandum was signed by ministers Kim Sung-whan and Alparslan Bayraktar.

Turkey plans four reactors at Sinop as its second nuclear plant, aiming to generate electricity before 2035, plus four more in Thrace; Korean firms are competing for the business, and Tuesday's documents commit both governments to "proactively support South Korean companies' participation." On defence, the summit formalised months of groundwork: a joint industry-and-logistics committee met in July, building on the Altay tank programme, developed with Hyundai Rotem's technical support and a South Korean engine and transmission, followed by a September letter of intent on naval vessels. Trade hit a record $10.7 billion last year under a free trade agreement in force since 2013; the leaders target $15 billion and an update of that agreement.

The blanks the joint statements left

What will Sinop actually cost; and who pays?

Neither side disclosed a price for the four Sinop reactors, the financing terms Korea's Eximbank might offer, or a timetable for a final investment decision. It is not public whether KEPCO is now the preferred partner or still competing against other bidders, the statements speak of "supporting" Korean participation, not of an award, and the ownership model for Sinop remains unannounced. Turkey's first plant, Akkuyu, was built by Russia's Rosatom under a build-own-operate structure.

The defence pledges are equally thin on detail: no country, contract value or programme was attached to the third-market ambition, the promised trade-agreement update has no published scope or deadline, and what Turkey's reaffirmed support for South Korea's North Korea policy means in practice was left to communique language.

Ankara's reactors, Seoul's export engine

For Turkey, Sinop is the second leg of a nuclear programme meant to cut dependence on imported gas and anchor electricity supply on the Black Sea coast. Four reactors there, plus four planned for Thrace, would make nuclear a structural pillar of the energy mix; which is why Ankara wants a partner bringing both reactor technology and financing. The recent tempo of Turkish diplomacy shows a country widening its partnerships rather than narrowing them.

For South Korea, the summit showcases its nuclear export drive: KEPCO and its supply chain are hunting the next large overseas reactor order, and a government-to-government financing framework is what turns a bid into a bankable project. The Eximbank memorandum is therefore the day's most consequential signature; it converts political goodwill into credit capacity. The same logic runs through defence: two mid-size powers with serious arms industries agreeing to sell together into third markets. In a world where the major powers are racing for energy and technological leverage and energy disruptions are redrawing trade routes, a Seoul–Ankara industrial axis is a bet that the middle of the map can set some of its own terms.

The middle-power bargain: reactors for reach

Read through the five dimensions, the summit is less about one power plant than about how two middle powers position themselves. Geopolitically, Turkey is diversifying partnerships, deepening ties with a US-allied Asian industrial power while keeping its multi-vector foreign policy, and South Korea is converting industrial strength into diplomatic capital far beyond its region. Economically, the real deliverable is financial: reactors are won on credit terms, not brochures, and the Eximbank memorandum signals Seoul will underwrite its champion.

Technologically, the agenda stretches past concrete and turbines; biotechnology, critical minerals, semiconductors, artificial intelligence and a first-ever joint science committee aim to braid the two innovation systems together. Historically, the partnership draws on unusual depth: Lee invoked "deep friendship and trust forged in blood," a reference to the Turkish brigade in the Korean War. Industrially, both countries field large export-oriented manufacturing workforces; the Altay tank, Korean engines inside Turkish armour, is the physical emblem: co-produce at home, sell abroad together. The open question is whether the third-market defence ambition survives export-control politics: joint ventures are easy to announce, but joint exports need aligned licensing regimes and willing customers.

What moves after the handshakes

The first ripple runs through the Sinop tender: with a Korean state-backed financing framework on the table, rival bidders face a competitor offering Ankara technology plus credit in one package. How contenders respond, and whether Turkey uses the Korean bid as leverage in parallel negotiations, will shape the plant's final cost and structure.

The second runs through the defence market. A Korean-Turkish co-production and co-export pipeline, built on the Altay and Fırtına precedents and the new naval track, would put a new mid-tier supplier bloc into competitions across the Middle East, Central Asia and Southeast Asia. Incumbent exporters will read the Seoul language on "joint inroads into a third market" as a declaration of intent.

The third is institutional: a first Joint Science and Technology Committee, a trade-agreement update in prospect and a $15 billion trade target give the relationship a standing bureaucratic rhythm. Summits fade; committees compound. If the financing assessments now underway convert into term sheets, November 2026 will be remembered as the day Sinop stopped being a memorandum and started being a pipeline.

The calendar that decides Sinop

When will Ankara name its Sinop partner?

The preliminary feasibility study, site evaluation via the joint working group, is the immediate track to watch: its conclusions on cost and schedule will determine whether the Korean bid advances from "supported" to selected. The Eximbank's financing feasibility assessments, now mandated by the new memorandum, will set the credit terms Ankara can count on; the variable most likely to decide the tender.

Erdogan's three-day state visit continues, with further business and defence engagements expected. Watch for KEPCO or Turkish energy ministry statements on the study's timeline, the convening date of the first Joint Science and Technology Committee, and movement on the trade-agreement update. The next hard data point is the feasibility readout; everything until then is positioning.