ICJ Admits Guatemala into Sapodilla Cayes Sovereignty Dispute

The International Court of Justice has unanimously ruled that Guatemala may intervene in the case between Belize and Honduras, inserting a third claimant into a territorial dispute over some of the Caribbean’s most contested island territory.

The Sapodilla Cayes is a cluster of small Caribbean islands in the Gulf of Honduras that all three nations claim as their own. The court’s decision, delivered at the Peace Palace in The Hague, does not resolve the underlying question of who owns the islands. That merits hearing still lies ahead. But the ruling dramatically changes the shape of those proceedings, allowing Guatemala to appear before the court, not as a full party but as a non-party intervener, specifically to protect its legal interests and inform the court of the nature and extent of its own competing claim.

The Sapodilla Cayes are a small group of uninhabited and semi-inhabited coral islands situated where the coastlines of Belize, Guatemala and Honduras converge in the Gulf of Honduras. Their strategic and legal importance far exceeds their modest size.

Belize has administered the cayes since independence and bases its claim on the continuous and peaceful exercise of sovereign authority by Britain, to which it succeeded, together with what it says was Honduras’s acquiescence. Honduras, which calls the islands the Cayos Zapotillos, claims title through Spain, asserting it inherited Spanish sovereignty and has itself continuously exercised authority and effectivités over the territory.

Guatemala’s claim runs on a parallel track. In a separate ICJ case, Guatemala’s Territorial, Insular and Maritime Claim (Guatemala/Belize), Guatemala has submitted an all-encompassing territorial and maritime claim against Belize that includes, among other things, sovereignty over these same cayes. Guatemala’s position, like Honduras’s, is grounded in alleged succession to Spanish colonial title.

The result is that the same small cluster of islands is simultaneously the subject of two separate ICJ cases, with three different countries each asserting they hold sovereignty.

Guatemala filed its application to intervene in December 2023, under Article 62 of the ICJ Statute, which allows a third state to seek permission to participate in proceedings where it has an interest of a legal nature that may be affected by the court’s eventual decision.

Guatemala was careful to frame its application narrowly. It was not seeking to have the court rule on its own sovereignty over the cayes in the Belize–Honduras case. Rather, it sought to appear before the court for two specific purposes: to protect its legal interests, and to inform the court of the nature and extent of those interests, so that the court’s determination in the Belize–Honduras case would not inadvertently prejudice Guatemala’s position in its own separate case with Belize.

Belize raised no objection to the application. Honduras objected strenuously, arguing that Guatemala had failed to identify a sufficiently precise legal interest, that its application was redundant given the parallel proceedings, and, most pointedly, that it amounted to an abuse of the court’s procedural mechanisms.

The ICJ rejected Honduras’s arguments at every turn and found Guatemala’s application satisfactory on all four conditions required under Article 62 of the Statute and Article 81 of the Rules of Court.

On the core question, whether Guatemala had demonstrated a legal interest that may be affected, the court found Guatemala’s claim was a “real and concrete claim” to sovereignty, grounded in law, not merely political or strategic. The existence of Honduras’s competing claim, combined with the court’s need to actually decide who holds sovereignty, meant the ruling could directly touch Guatemala’s position in its separate case with Belize.