The End of a Sea Boundary Dispute: Romania vs Ukraine (ICJ 2009)

“Did countries split over one tiny island?” A real maritime boundary war over a single rocky islet— the International Court of Justice (ICJ) delivered a decision that surprised everyone. 🌊

Hello ⚖️ Let’s unpack an international law story the easy way. In 2009, the two European countries Romania and Ukraine locked horns over a patch of sea. “Who gets more of the waters?”—the decision ultimately landed in the hands of the International Court of Justice (ICJ). This case wasn’t just a quarrel at sea; it showed how much meaning a tiny island can carry. Now, let’s walk through this maritime boundary drama step by step.

Contents

1. How It Began: A Small Island, A Big Sea 2. The ICJ Steps In 3. Key Legal Issues: Island or Rock? 4. The ICJ’s Judgment and Outcome 5. What Changed After: Romania’s Win and Cooperation 6. What We Can Learn

How It Began: A Small Island, A Big Sea

It all started with a tiny rocky islet called Serpents’ Island. It sits in the northwestern Black Sea, between Romania and Ukraine. The island is small, but the surrounding waters were believed to hold significant oil and natural gas reserves. So the two countries disagreed for decades over “how far an island like this can project maritime zones.” Romania argued, “It’s just a rock—no independent maritime entitlements!” Ukraine countered, “It’s our territory, and of course it brings maritime zones with it!” When negotiations collapsed, Romania brought the dispute to the ICJ in 2004.

The ICJ Steps In

To resolve the dispute fairly, the ICJ followed several steps. It examined the lengths of the coasts, the location of the island, economic interests, and more, then had to draw an “equitable maritime boundary.” The table below summarizes the main steps in the proceedings.

Step	Description
Step 1: Application Filed (2004)	Romania officially filed a case against Ukraine with the ICJ
Step 2: Written Pleadings & Evidence	Both sides submitted charts, satellite data, and interpretations of international law
Step 3: Oral Hearings	International law experts argued before the ICJ judges
Step 4: Judgment (2009)	The ICJ fixed a single maritime boundary, ending the dispute

The case lasted about five years, during which both states respected international legal procedures and resolved the matter peacefully— a textbook model for international dispute settlement.

Key Legal Issues: Island or Rock?

The crux of the case was how to treat “Serpents’ Island.” Under the UN Convention on the Law of the Sea (UNCLOS), “rocks which cannot sustain human habitation or economic life of their own shall have no exclusive economic zone.” The ICJ focused on the following questions:

• Whether Serpents’ Island is a “habitable island” or merely a “rock”
• Whether waters around the islet could generate an independent EEZ
• Drawing an equitable maritime boundary reflecting the proportional lengths of the coasts

This debate symbolized how a small natural feature can have outsized legal consequences in international law.

The ICJ’s Judgment and Outcome

On February 3, 2009, the ICJ delivered its final judgment. The key finding: Serpents’ Island is closer to a rock. That is, it cannot sustain human life or independent economic activity, so the islet cannot generate its own exclusive economic zone (EEZ). However, a 12-nautical-mile territorial sea was recognized.

As a result, the ICJ allocated about 80% of the disputed maritime area to Romania, with Ukraine receiving the remaining 20%. Strikingly, the decision was accepted as “fair” by both sides. Rather than creating winners and losers, it became a symbol of “peaceful, law-centered resolution.”

What Changed After: Romania’s Win and Cooperation

Following the judgment, Romania began oil and gas exploration in its newly confirmed Black Sea zones, while Ukraine respected the ruling and chose a path of peaceful cooperation. The decision has been hailed as a model for “resource development without conflict.” It is frequently cited in other maritime boundary disputes.

Party	Outcome
Romania	Secured new maritime zones; launched energy exploration
Ukraine	Expressed respect for international law; relations stabilized
International community	Praised as a fair application of the law of the sea

The two countries then worked to mark the boundary clearly in the Black Sea and discussed joint management of marine resources— a rare case where “peace through law” took tangible form.

What We Can Learn

This ruling wasn’t merely a contest between states; it showed that “international law can solve real-world problems.” Key takeaways:

• Even a small, remote islet can be central to an international dispute.
• International law resolves issues with logic, not force.
• Fair procedures can produce outcomes both sides can accept.

Frequently Asked Questions

Who holds Serpents’ Island now?

Today, Serpents’ Island (Zmiinyi Island) is Ukrainian territory. The ICJ ruling did not address sovereignty over the islet—only the “effect of the islet” on the maritime boundary.

Why was it treated as a “rock,” not an “island”?

Under UNCLOS Article 121, rocks that cannot sustain human habitation or economic life of their own cannot generate an EEZ. Serpents’ Island lacks fresh water and arable land and is classified as a “naturally uninhabitable area.”

Did this ruling influence other countries’ disputes?

Yes—significantly. The case is cited in many maritime boundary disputes as a benchmark for limiting the impact of small islets. It has also been referenced in East Asia and the South China Sea.

How did both countries react after the ruling?

Romania welcomed the decision as “fair,” and Ukraine respected and accepted the ICJ judgment. The case remains a symbol of “resolution without conflict.”

By what method does the ICJ draw maritime boundaries?

The ICJ uses a three-stage approach: ① Construct a provisional equidistance line → ② Adjust for relevant circumstances → ③ Disproportionality check. This yields a fair and balanced boundary.

What’s the main lesson from this case?

That “dialogue and law” can be stronger than force in international disputes. The case shows that reasonable outcomes are possible without military confrontation.

In Closing

It’s surprising that a tiny islet can determine lines across a vast sea. But in Romania vs Ukraine, it wasn’t about “who is stronger,” it was about how persuasively you argue what is fair. Through a firm method—equidistance → relevant circumstances → proportionality—the ICJ untied a knot of emotions and drew a line both sides could accept. Thanks to that process, the parties could develop resources without inflaming the dispute. It’s not so different in everyday life: when opinions diverge, setting principles and talking through evidence makes relationships stronger. The power of law isn’t distant. As with today’s sea story, when reason and respect meet, even complex problems find a course. 🌊💜