The dispute stems from islands formed by sedimentation in the Amazon River after the Rio de Janeiro treaty was signed. On Tuesday, President Gustavo Petro accused Peru of seizing Colombian territory in the Amazon, violating the Rio de Janeiro Protocol, which ended the war between the two countries from 1932 to 1933.

“Peru has taken over a territory that belongs to Colombia and has violated the Rio de Janeiro Protocol… That agreement established that the border is the deepest line of the Amazon River and that any disagreement would be resolved between the parties,” Petro said.

The dispute stems from islands formed by sedimentation in the Amazon River after the treaty was signed. Petro said these islands are “north of the current deepest line,” and that the Peruvian government “has just claimed them through legislation and placed the capital of a municipality on land that, under the treaty, should belong to Colombia.”

“This unilateral action, in violation of the Rio de Janeiro Protocol, could eliminate Leticia as an Amazon port, stripping it of its commercial lifeline. The Colombian government will first and foremost use diplomatic channels to defend national sovereignty,” Petro said.

He announced the issue would be discussed Thursday in Leticia, the capital of the Amazonas department, during the National Army Day celebration commemorating the Battle of Boyaca, which sealed Colombia’s independence.

In July 2024, Diego Cadena, then-director of Territorial Sovereignty at Colombia’s Ministry of Foreign Affairs, said that Santa Rosa Island does not belong to Peru and was being irregularly occupied. He also rejected the authority of the island’s mayor, Peruvian Ivan Yovera.

The Peruvian government responded by filing a protest with Colombia’s charge d’affaires in Lima and reaffirmed “sovereignty and jurisdictional rights over Santa Rosa Island.” However, then–Peruvian Foreign Minister Javier Gonzalez-Olaechea declared the matter closed on July 15, 2024, expressing “satisfaction” with the Colombian government’s response to Peru’s diplomatic protest.

Santa Rosa Island, located near the tri-border area of Peru, Brazil, and Colombia, is home to about 3,000 residents who primarily engage in commerce.

“Santa Rosa de Yavari Island: Triple border nerve (map). The Santa Rosa de Yavari island, located in the Amazonas River, in front of Leticia (Colombia) and Tabatinga (Brazil), is a Peruvian territory that arose towards the 1970s due to a natural process of fragmentation of the island of Chineria. This Tuesday, the space has once again sought after the pronouncement of Gustavo Petro.”

Colombian Foreign Ministry’s Arguments

In a statement, Colombia’s Foreign Ministry said that Santa Rosa Island formed later within the course of the Amazon River, following the only official island allocation between the two countries in 1929.

“For Santa Rosa Island and others that have emerged since 1929, an allocation process must be carried out by mutual agreement between the foreign ministries, according to the arrangements reached by both countries,” the ministry said.

“To that end, Colombia and Peru established the Permanent Joint Commission for the Inspection of the Colombia–Peru Border (Comperif). For years, Colombia has insisted on the need for bilateral work to assign islands and has reiterated that Santa Rosa Island has not been assigned to Peru,” it added.

The statement also noted that following the enactment of the “Law for the Creation of the Santa Rosa de Loreto District in the Province of Mariscal Ramon Castilla, Loreto Department,” Colombia has issued formal diplomatic protests to the Peruvian government, requesting the reactivation of Comperif “as soon as possible to determine the sovereignty of the islands that emerged in the Amazon River after 1929.”