The Istanbul Agreement and the Black Sea Grain Corridor: How a Diplomatic Note Became 33 Million Tons of Grain

Why It Matters

The Black Sea Grain Initiative was a time-limited, UN-supported arrangement that let commercial ships leave three Ukrainian ports during the war, under a joint inspection regime hosted in Istanbul. Between August 2022 and July 2023 it moved roughly 33 million metric tons of grain and other foodstuffs. It is the clearest recent example of belligerents agreeing on a narrow, verifiable humanitarian-commercial mechanism through a third-party host. Its lapse shows how fragile such deals are when they depend on linked commitments.

Background

Why the corridor was needed

Russia's full-scale invasion of Ukraine on 24 February 2022 and the resulting naval situation halted most commercial shipping from Ukraine's Black Sea ports. Ukraine and Russia are both major exporters of wheat, maize, sunflower oil and (in Russia's case) fertilizer. The UN and the World Food Programme warned that stranded cargoes and higher prices would hit import-dependent countries in the Middle East, North Africa and East Africa.

Türkiye controls the Bosporus and Dardanelles under the 1936 Montreux Convention. This made it a natural venue and logistical hub. For the wider legal setting, see The Global Anatomy's review of Montreux and Black Sea mediation.

Chronology

The legal form: mirrored texts and a linked memorandum

The package was not a single document signed by Russia and Ukraine together. It consisted of a Russia–Türkiye–UN text and a Ukraine–Türkiye–UN text with matching content, plus a separate Memorandum of Understanding between Russia and the UN Secretariat on facilitating Russian food and fertilizer exports. This structure let the two sides avoid direct bilateral signature while committing to the same operating rules. It also meant Russia's complaints later centred on the memorandum, not on the Ukrainian-port mechanism itself.

The arrangement had an initial term of 120 days and was designed to continue automatically unless a party objected. Each side pledged not to attack the vessels, ports and facilities involved.

How the mechanism worked

1. Registration. Commercial shipowners and charterers submitted vessel and cargo details to the JCC. The JCC, staffed by officials from Russia, Ukraine, Türkiye and the UN, approved vessels, schedules and routes.
2. Inspection. Joint inspection teams, made up of representatives of the four parties, boarded ships in the Istanbul anchorage area. Inbound vessels were checked to confirm they carried no cargo or weapons. Outbound vessels were inspected to confirm that cargo was agricultural produce or foodstuffs.
3. Transit. Cleared vessels sailed to and from the ports of Odesa, Chornomorsk and Pivdennyi (Yuzhny) along a designated maritime humanitarian corridor, with Ukrainian pilots guiding them through the approaches.
4. Monitoring. The JCC tracked movements and resolved disputes, and a message channel existed to notify the parties' militaries of ship movements.
5. Onward passage. Loaded ships then transited the Bosporus as ordinary merchant vessels under Montreux's freedom-of-passage rules for commercial shipping.

Results

According to the UN's JCC reporting, about 33 million metric tons of grain and foodstuffs had left Ukraine under the arrangement by mid-July 2023 on over 1,000 voyages, going to dozens of countries. Maize and wheat made up most of the volume, with sunflower products and other commodities making up the rest. The WFP also chartered cargoes, including wheat bound for Afghanistan, Ethiopia and other emergency operations. The UN and analysts linked the arrangement to a decline in global food price indices from their spring 2022 peak, although other factors also affected prices.

For a parallel treatment of the mechanics and the ending, see Doctrine Review's explainer on how the initiative worked and why it ended.

Key Players & Positions

Russia

Moscow's stated position, made by President Putin, the Foreign Ministry and the Kremlin spokesman, is that the grain track was only half of a package. It argues that the memorandum on its own agricultural and fertilizer exports was never implemented in practice. Russian officials cited problems with payments, including the reconnection of Rosselkhozbank to the SWIFT messaging system, with shipping insurance and port access, with the supply of spare parts and equipment, and with the resumption of the Togliatti–Odesa ammonia pipeline. Russia also argued that too little of the grain reached the poorest countries. Moscow said it would return if its conditions were met. On 19 July 2023 the Russian Defence Ministry declared that ships heading for Ukrainian ports would be treated as potential carriers of military cargo.

Ukraine

Kyiv's official statements, from President Zelensky and the Ministries of Foreign Affairs and Infrastructure, describe the initiative as a vital export route that supported the Ukrainian economy and global food security. Ukraine maintained that it had met its obligations and that Russia's demands concerned separate sanctions-related issues. After the lapse, Ukraine said it would seek to keep exports moving by other means, and in August 2023 it announced its own temporary corridor along its coastal waters, relying on its own assessments of risk.

United Nations

Secretary-General Guterres and UN officials, including UNCTAD Secretary-General Rebeca Grynspan, who led UN work on the Russian memorandum, said the Russian-side facilitation was being pursued in parallel and that the UN had put proposals to Moscow. On the day of the lapse, the Secretary-General expressed regret and said the arrangement had helped lower food prices, calling for its continuation. The UN also argued that Russian grain and fertilizer were never sanctioned as such, while acknowledging that banking, insurance and logistics channels were burdened by sanctions-related caution among private actors.

Source Comparison

International media often framed the deal as a UN achievement with Turkish hosting, and its lapse as a Russian decision. Russian outlets emphasised the unmet memorandum. Turkish sources emphasise that a single venue and a trusted channel made the agreement possible. The primary documents, JCC statistics and each party's own statements are the best basis for assessment. For a sourcing method, see Editorial Principles.

Another view is offered by Interstate Journal's account of how Türkiye helped broker the deal, among others.

Key Terms & Related Guides

• Joint Coordination Centre (JCC): the Istanbul-based body with Russian, Ukrainian, Turkish and UN officials that approved vessels and routes and oversaw inspections.
• Black Sea Grain Initiative: the 22 July 2022 arrangement for exports from Odesa, Chornomorsk and Pivdennyi.
• Memorandum of Understanding (Russia–UN): the parallel text on facilitating Russian food and fertilizer exports.
• Montreux Convention (1936): the treaty governing passage through the Turkish Straits in peace and war; Article 19 covers belligerent warships, while commercial passage is generally free.
• Mirrored texts: matching agreements signed separately by Russia and Ukraine with Türkiye and the UN.

Related reading on Diplomat Note: Diplomat Note home, About Diplomat Note, What Is a Note Verbale?, COP31 and Zero Waste and Reader FAQ.

Diplomat Note presents analysis from a Türkiye-informed perspective, grounded in Türkiye's official legal and strategic positions. Claims are attributed to primary sources such as treaty texts, UN and IOC-UNESCO documents, official archives and public statements, so that readers can verify them independently. — Diplomat Note Editorial Team