Venezuela gambles on jurisdiction fight as Guyana eyes oil prize beneath disputed territory

Caracas has told the International Court of Justice it lacks authority over a boundary dispute that Guyana argues was settled in 1899, a procedural gambit that masks a high-stakes contest over a territory holding an estimated 11 billion barrels of oil.

By Monexus Staff Writeramericas5-minute read6 May 2026☆ Save ↗ Share ⎙ Print

Venezuela has told the International Court of Justice it has no jurisdiction to hear Guyana's boundary claim, escalating a decades-long dispute that has acquired new urgency since major offshore oil discoveries turned the Essequibo region into a potential prize worth many billions of dollars.

Caracas filed its position with the court on 6 May 2026, arguing that the ICJ lacks authority to adjudicate a dispute it contends was manufactured after a 2015 oil find by ExxonMobil in waters adjacent to the disputed territory. Guyana, which has held effective administration of the region since colonial times, argues the court has clear jurisdiction under a special agreement the two countries signed in 1997 and a 1966 instrument confirming the 1899 treaty that originally defined the boundary. The court had previously ruled in October 2023 that it could proceed, a determination Venezuela is now seeking to reverse.

The timing is not incidental. The Essequibo dispute has lain dormant for most of its modern history; what has animated it now is not archaeology or national honour alone but the contents of the seabed below and to the east of the territory. ExxonMobil's Liza field, discovered in 2015, sits in Guyanese-claimed waters outside the Essequibo itself but within a zone that Georgetown asserts is a function of where the land boundary falls. Three additional major discoveries followed. Together they constitute one of the largest new hydrocarbon provinces in the Western Hemisphere.

The legal architecture of a land claim

Guyana's claim rests on a treaty signed in Washington on 3 October 1899, which drew the boundary between British Guiana and Venezuela at the Essequibo River — a line that gave Georgetown roughly 80 percent of the territory in dispute today. Venezuela accepted that line for six decades before repudiating it in 1962, citing fraudulent survey work and newly surfaced Spanish colonial documents. The 1966 Geneva Agreement, brokered by Brazil, the United Kingdom, and the United States, established mechanisms for resolution but produced none. A mediation effort collapsed in 2014. Georgetown then filed with the ICJ, which has since received submissions from both sides on jurisdiction and merits.

The core of Venezuela's argument is that the 1899 treaty was not a concluded agreement but an ongoing negotiation, and that the ICJ cannot inherit jurisdiction from a process Venezuela never accepted as binding. Caracas also argues that the Geneva Agreement was superseded by subsequent bilateral engagement — a contention Georgetown contests sharply. What is not in dispute is that Venezuela has never controlled the Essequibo in living memory; the region has been administered as part of Guyana since the colonial period.

The oil overlay

The discovery of the Liza field and its successors by ExxonMobil — operating under a concession with Georgetown — transformed what had been an academic dispute between two small states into something the major powers began watching closely. The Stabroek Block, where the discoveries cluster, lies in Atlantic waters east of the Essequibo but north of where the river mouth would place the maritime boundary. Guyana argues the Liza field sits entirely within its exclusive economic zone. The case before the ICJ will ultimately determine whether the riverain baseline from which those maritime claims derive runs along the Essequibo's current course or a more easterly line — a distinction worth, by some estimates, the better part of 11 billion barrels in remaining reserves.

ExxonMobil's presence complicates the diplomatic calculus for both governments. Venezuela has periodically threatened action against ExxonMobil's operations, including a 2023 decree that purported to declare a "security zone" around the Stabroek Block, though the decree's legal standing was unclear. The company has continued operations and expanded production. For Caracas, the oil dimension raises the reputational stakes: a ruling that affirms the 1899 boundary would legitimise, in Venezuelan eyes, a carve-up conducted by colonial powers over Venezuelan territory — and would hand the benefits of that carve-up to a Western oil major operating under a concession from a government Venezuela considers an occupying power.

The structural frame

What is playing out at the ICJ is, at one level, a legal argument about treaties and jurisdiction. At a broader level it is a case about how boundaries drawn by empires are renegotiated in a world where the resources they once ignored have acquired enormous value. The colonial boundary regime in South America largely held after independence; where it has frayed, the causes have typically been either strategic reconsideration by a great power or the discovery of valuable subsoil assets. Neither Venezuela nor Guyana created this dispute — colonial administrators did — but both states now have acute interests in its resolution, and neither can afford to lose.

For the United States, the case presents an awkward posture: ExxonMobil is a US company operating under a contract with an ICJ claimant, in a region where Washington generally backs Caribbean stability. For Brazil, which shares a border with both Guyana and Venezuela, the stakes are regional security and the integrity of the Amazon basin that the Essequibo partly drains. Neither power has publicly taken sides on the merits, though both have significant interests in an orderly resolution.

The stakes ahead

The jurisdiction challenge is a procedural gambit, not a merits argument. Even if the ICJ rules against Venezuela on this point, the case on the boundary itself could take years more to resolve. But the outcome will shape investment conditions across the wider Caribbean littoral and set a precedent for how post-colonial boundary claims are handled when they collide with modern resource economics. If the ICJ affirms jurisdiction and proceeds, it will be issuing its ruling against a background where the disputed territory's seabed is already producing oil under a concession both sides contest.

The broader question — whether an agreement reached by colonial administrators in 1899 between Britain and Venezuela, without Venezuelan participation, can form the basis of an international legal order — is one the court has not yet answered. What is clear is that neither Caracas nor Georgetown is prepared to leave the question unanswered.

This publication's coverage of the Essequibo dispute has consistently centred the colonial history of the boundary rather than treating it as a bilateral dispute of equal standing — a framing that the available sources on both sides' legal arguments support.

Wire provenance

This editorial synthesis draws on the following public wire/social posts:

http://reut.rs/4d3njF7