Foreign Relations & International Law

A New Strategy for the Black Sea

Bradford Dismukes, Barry Blechman
Wednesday, June 14, 2023, 4:00 AM
With a little help from its friends, Ukraine can guard its maritime security in the Black Sea and protect its critical grain exports.
Ukrainian patrol boats participate in a display in Odessa, Ukraine, for Ukrainian Navy Day on July 7, 2019. Photo credit: U.S. Navy photo by Mass Communication Specialist 1st Class Kyle Steckler/Released/Public Domain via DVIDS.

Published by The Lawfare Institute
in Cooperation With

Editor’s Note: Since the war began in 2022, Ukraine has fitfully exported its grain to the world market, with Russia often interrupting, or threatening to interrupt, this flow. Foreign policy experts Bradford Dismukes and Barry Blechman argue that the United States and its allies should work with Ukraine to establish a Black Sea shipping corridor, counter-blockade Russian forces, and create an international convention to ensure the region's food products will reach world markets. 

Daniel Byman


Roughly 40 percent of Ukraine’s exports are agricultural products, especially grain, the vast majority of which move by ship over the Black Sea. At the start of its invasion in early 2022, Russia attempted to stop these shipments, which prompted an outcry from developing nations, such as Egypt aand Lebanon, that are dependent on Black Sea food and fertilizer to feed their populations. In response, Russia agreed in July 2022 to a “grain initiative” brokered by the United Nations and Turkey. The initiative permits Russia to inspect ships arriving at three Ukrainian ports to ensure they are not delivering arms, and then—once loaded—move through a specified maritime corridor to exit the Black Sea. Russia manipulates the initiative frequently and at will, slow-rolling its inspections and approvals. It also has threatened repeatedly to suspend the initiative, most recently in May. Although negotiations succeeded in extending the current arrangement, since November Russia has only permitted renewals to last for 60 days. Russia’s frequent delays of incoming ships and continuing threats to suspend the initiative have driven up Ukraine’s costs and reduced the country’s earnings significantly.

Ukraine should seek an alternative to bypass these problems and reinforce its maritime security. An effective political and military strategy would have three key components: 1) establish a near-shore shipment corridor in the Black Sea defended by Ukraine and NATO; 2) initiate a Ukrainian counter-blockade of Russian naval forces; and 3) propose an international convention to guarantee the unfettered export of all the region’s grain and other foodstuffs. These synergistic plans reflect enduring geopolitical and economic realities. Their combined effect is greater than the sum of the parts, but each prong of the strategy stands on its own and should be pursued on its own right.

Corridor for Grain Shipments

The highest military priority would be to establish a near-shore, grain-ship corridor, from Odessa to the Bosphorus. The proposed route would be entirely within the territorial waters of Ukraine and NATO member states.

Proposed near-shore corridor to provide Ukrainian ships access to the Bosphorus. Yellow areas show Ukrainian territorial waters to be defended by Ukrainian forces; red areas show territorial waters of Romania, Bulgaria, and Turkey, to be defended by NATO. Image credit: Authors.
Proposed near-shore corridor to provide Ukrainian ships access to the Bosphorus. Yellow areas show Ukrainian territorial waters to be defended by Ukrainian forces; red areas show territorial waters of Romania, Bulgaria, and Turkey, to be defended by NATO. Image credit: Authors.

The portion of this proposed corridor in Ukraine’s territorial waters would be Ukraine’s responsibility to defend; the rest of the route should be secured by NATO to create a seamless means of access. To protect the corridor, NATO would provide purely defensive armaments to Ukraine, Romania, Bulgaria, and Turkey—specifically, minesweepers, minelayers, and anti-submarine mines to counter Russia’s undersea threat; land-based anti-surface ship missiles; land-based air/missile defenses, possibly with sea-based early warning enhancement; and, as needed, NATO’s best electronic warfare for cover and deception.

NATO’s actions, as envisioned in the strategy, would be the least escalatory measures conceivable. They would pose no threat to Russia’s territory or its regime. Nor would NATO nations be required to engage Russian forces unless they were used to attack ships within NATO’s territorial waters. NATO-Russia combat at sea would be nearly impossible, unless Russia chose to attack, which would be highly unlikely given the decimated state of its Black Sea Fleet (BSF). The larger purpose of the corridor would be humanitarian: It would keep Ukraine’s grain flowing to world markets. These measures would be entirely consistent with the Montreux Convention, which allows riparian states to provide for their own self-defense. And the small ships that would be provided to Romania, Bulgaria, and Turkey would not justify a Russian reinforcement of its forces. Reinforcing these states’ access to the Sea of Marmara has been a long-term concern, and assessments dating back more than 70 years argue that modest reinforcements would not generate a Russian response.

A defended near-shore corridor is vital to Ukraine’s security. The nation must have access to the sea for its export-dependent economy to function. Odessa is Ukraine’s jugular; without its exports, Ukraine’s economy would be strangled. Given increasing political discomfort about the cost of the war in the United States and other Ukrainian allies, it seems clear that NATO would not support a dying economy and a large-scale war effort for very long.

Despite the overwhelming focus on the territorial shifts in the land war, Ukraine could lose the war through action at sea. If, following settlement of the current conflict, Russia were to invade Ukraine again, it would not repeat its strategic mistake of 2022 and instead would attempt to mount a sustained naval blockade of Odessa. But in the near term, Russia is weak at sea and so will push over land, west from Kherson to try to seize Odessa.

Russia’s threats to suspend or withdraw from the UN deal are not credible, but are nonetheless effective because of the “insurance effect.” Attacking merchant ships, or threatening to do so, causes international insurance companies—notoriously risk-averse—to end or charge astronomical rates for coverage. For example, Reuters reported in January that Lloyd’s Black Sea rates increased 20 to 25 percent at the start of the year. When insurance becomes inaccessible or unaffordable, merchant ships stop sailing.

Militarily, Russia may lack the physical means to interdict ships carrying Ukrainian grain even today. Any effort in the future could be defeated by Ukrainian and NATO forces defending the near-shore corridor. Politically, Russia faces insurmountable disincentives against withdrawing from current arrangements. It has negotiated, signed, and thrice renewed the UN agreement. It cannot now reverse course and attack grain-laden ships sailing from Odessa. Doing so would eviscerate the humanitarian propaganda that it has promoted diligently since the agreement was first announced in July 2022. Moreover, it would add further to the NATO consensus on the need for the near-shore grain corridor and its international acceptance.

Ukraine can and should end Russia’s continuing manipulation of the existing UN arrangement. It can demand that the initiative be modified to guarantee passage of Ukrainian grain ships sailing via the defended, near-shore corridor. Western governments should intervene in international insurance markets, becoming reinsurers of last resort, as the United States did during the Persian Gulf “Tanker War” in the 1980s, to cover ships sailing in the corridor. NATO can and should immediately demonstrate its intent to join Ukraine in defending the corridor, which would do double duty as a strategic glacis—a protective barrier on a strategic scale—defending NATO’s southern flank while providing an enduring lifeline for Ukraine.

Ukraine’s Counter-Blockade

With material and political support from the United States and other allies, Ukraine should declare its intention to mount a counter-blockade against the BSF. Ukraine’s counter-blockade would be executed with close-in minefields laid, surveilled, and defended by uncrewed surface vessels (USVs). This idea was also recently suggested by analysts at the RAND Corporation.

USVs are a new dimension of naval warfare. Ukraine’s versions appear to be simple, inexpensive, and effective. Its USVs have already successfully attacked Russian naval vessels in the approaches to Sevastopol harbor and harassed Russian merchant ships near the Kerch Strait. Russia withdrew most of the BSF east to Novorossiysk because Ukraine’s USVs, along with its anti-surface ship missiles, have transformed the situation. The BSF, its sea-based cruise missiles aside, had become little else than an exposed and useless vulnerability.

Ukraine’s counter-blockade would focus on naval forces at bases in Sevastopol and Novorossiysk. It would explicitly exclude merchant ships carrying grain, fertilizer, and other food products. South of Novorossiysk (Sevastopol does not export grain) Ukraine would designate and provide such ships a safe, near-shore corridor in Russia’s territorial waters, and they would register with and follow appropriately modified rules of the now-existing UN Joint Coordination Center in Istanbul. The plan would exactly mirror that followed by ships carrying grain from Ukraine today.

The primary military purpose of the blockade would be to neutralize the BSF on behalf of achieving Ukraine’s territorial objectives in the south. Sinking the BSF seems unlikely, although Ukraine already has reduced its size to fewer than 20 surface combatants, three of which carry missiles, and just two to four submarines. Instead, the blockade would be a war of attrition at sea in which a successful outcome would tie up the Russian fleet on defense and prevent it from carrying out any other missions at acceptable rates of losses to Ukrainian forces. Human casualties on the Ukrainian side would be minimal. A secondary objective would be to interdict Russian and shadow ships carrying military cargo into or out of Russia—for example, to Syria and beyond.

It is assumed that the West has on hand or can generate ample supplies of mines and that indigenous capacity to produce USVs in Ukraine has been or can be developed at scale, and/or USVs can be acquired from third parties like Turkey. A blockade war of this kind might be sustained for a lengthy period, possibly measured in years. Ukraine must also develop defenses against Russian USVs. The longer a blockade war lasts, the more its tactical and technological evolution must be addressed.

In sum, a Ukrainian counter-blockade seems feasible and could be an important element in a war-winning strategy at sea.

International Grain Export Convention

Announcement of Ukraine’s intention to blockade should be accompanied by demands that Russia agree to an International Grain Export Convention (IGEC), a more formal, multinational guarantee to replace the current grain initiative. Under it, all Black Sea states would agree not to interfere, under any circumstances, with the seaborne export of the region’s grain, other foods, and fertilizer. The IGEC would be signed and guaranteed by the great powers, including the United States, and would be opened for signature by all other nations.

A grain convention is not a radically new idea. It grows out of principles already being observed in the Black Sea: specifically, that war between states in the region should not be allowed to cause the starvation of millions of people in nations thousands of miles away, who are in no way parties to the war. That principle underlies the current UN grain initiative. The proposed IGEC  would expand its application to the Black Sea as a whole and would build on existing international mechanisms for its oversight and management, like the Joint Coordination Center in Istanbul established to support the current arrangement.

A grain export convention would be an essential companion to the Ukrainian counter-blockade. Ukraine would be fighting not only to defend its own exports; it would be fighting for the security of the exports of all Black Sea states, including Russia’s. Ukraine’s actions reflect recognition of the world’s dependence on grain exported from the Black Sea. Ukraine’s laudable humanitarian objective would generate near-universal international support—even Russia could not publicly oppose it.

However, Russia would likely make its acceptance of an IGEC conditional on a “poison pill” demand that the entry to the Black Sea of non-riparian navies be prohibited. In fact, such a situation has been in effect since the war started and, surprisingly, has been accepted tacitly by the United States and other NATO nations. Even though it would solidify Russia’s dominant position in the Black Sea, many nations might find this appealing—China, for obvious reasons, and the many additional nations who have remained neutral in the Russia-Ukraine war. Many might view it as a form of stabilizing arms control; after all, for more than a year NATO and Russia have avoided a broader conflict at sea, despite the raging war on land.

The continued exclusion of NATO from the Black Sea would obviously be unacceptable to Ukraine and the West. It would render an IGEC unenforceable if, following a truce, Russia were to restart the conflict. An IGEC would result in the re-entry of the navies of all NATO members under the most favorable conditions possible. In this event, NATO should restrict its maritime reinforcements to the small ships required to defend the grain corridor and mount the blockade of the BSF to avoid creating a precedent for Russia to reinforce the BSF with major combatants. It also would make it extremely difficult for Russia to use its threat of blockade as a bargaining chip in negotiations to end the war.

An IGEC proposal should be put forward immediately. Doing so would be essentially cost and risk free. International bodies are much concerned with food security, which is now recognized as having major implications for political stability, as well as meeting a deep humanitarian need. Any U.S. president would find that a grain export agreement has widespread appeal. It should be advanced as soon as possible—with proper acknowledgment of Ukraine’s central role in it.

In addition, a grain convention could reshape the strategic architecture of the Black Sea in Ukraine’s favor. The Montreux Convention benefits Russia, as it did previously for its biggest booster, the Soviet Union. A grain convention would have the effect of draining Montreux of some of its pro-Russian bias and blocking Russia’s possible path toward making the Black Sea a strategic point d’appui in the Balkans, in Syria to the south, and (with Iran’s enthusiastic support) in the Caspian and Central Asia to the east. An IGEC would make the Black Sea region a more stable place and Ukraine more secure within it, while garnering praise and support for Ukraine, the United States, and its allies. It should be put forward immediately, even independently of the other much needed actions proposed.

A Naval Advantage

With rare exceptions, such as the sinking of the BSF flagship Moskva, the major events of the war in Ukraine have emphasized the importance of territorial conflict—Ukraine’s battles to regain areas in the east and south lost in 2014, the further losses in the opening months of Russia’s offensive in 2022, and Russia’s brutal attacks on civilians and the destruction of Ukraine’s cities. Naval forces, however, could play a much larger role. Curiously, the conflict’s focus replicates the current U.S. National Security Strategy, which concentrates exclusively on ground, air, and space forces in considering how to confront Russia and China. Like the United States vis-à-vis the other great powers, Ukraine may be outgunned in the air and on the ground, but it has the advantage in the maritime arena. It should exploit this advantage through establishment of the “grain corridor” and a counter blockade of Russian ports to hasten the end of this tragic conflict.

Correction: A previous version of this article stated that the proposed corridor is the current route for Ukrainian grain exports. This is incorrect; the current route transits international waters.


Many of these proposals arise from online and live discussions over the last year of the Navy’s Strategy Discussion Group. For critique and general encouragement, the writers are indebted to Thomas M. Duffy, Mary Ellen Connell, James H. Bergeron, Steven T. Wills, and Ronald R. Harris. All are herewith absolved of responsibility for any misuse of their ideas.

Bradford Dismukes is a retired naval officer with an intelligence background. He analyzed Soviet and Russian naval doctrine and forces at the Center for Naval Analyses for 20 years.
Barry Blechman is the co-founder of the Stimson Center in Washington, DC. He has worked on international security issues for more than 50 years in the U.S. government, as well as in the non-profit and private sectors.

Subscribe to Lawfare