The International Court of Justice ruled on Monday that seven Caribbean islets belong to Colombia, ending a three-decade-long dispute between the Andean nation and Nicaragua.

"Colombia and not Nicaragua has sovereignty over the keys Albuquerque, Este Sudeste, Roncador, Serrana, Quitasueño, Serranilla and Bajonuevo," Court President Peter Tomka said as he read the verdict.

The ICJ had earlier confirmed Bogota's claim to the larger islands of San Andres, Providencia and Santa Catalina, part of an archipelago that lies 775 kilometers (480 miles) from mainland Colombia and 220 kilometers (140 miles) from the coast of Nicaragua.

While giving the islets to Colombia, Monday's decision also significantly expanded the waters under Nicaraguan control.

The ruling, which is not subject to appeal, allows Managua to claim an area extending outward 200 nautical miles from its Caribbean coast, with the exception of the waters immediately surrounding San Andres, Providencia and Santa Catalina.

The waters conceded to Nicaragua include lucrative fishing grounds and are what are thought to be substantial oil deposits.

The quarrel dates from 1980, when Nicaragua contended the 1928-1930 accords awarding sovereignty over the San Andres archipelago to Colombia was invalid because the Central American nation was under U.S. military occupation during the negotiations.