The U.N.'s highest court opened hearings on Monday into a bitter maritime border dispute between Nicaragua and Honduras, which almost triggered a war between the neighbouring nations in 1999, REPORTED REUTERS. Nicaragua first filed a claim with the International Court of Justice (ICJ) in 1999, asking the court to determine their mutual border in the Caribbean Sea which it argues has never been established, while Honduras claims it was set by the King of Spain in 1906 and upheld by the World Court in 1960. The disputed territory offers rich fishing waters and potential oil and natural gas reserves. Nicaragua maintains that its maritime border extends to 17 degrees North latitude, while Honduras claims its maritime border begins at 15 degrees North latitude. "Nicaragua has consistently maintained the position that its maritime Caribbean border with Honduras has not been defined," said Carlos Jose Gomez, representing Nicaragua at the court. "The fact is that Honduras has fabricated a non-existent traditional line," he added. Tensions have frequently flared between Nicaragua and Honduras, who were foes for much of the 1980s when the United States beefed up Honduras' military and air force and used its main Central American ally as a base for the Contra rebels it funded to fight Nicaragua's Marxist government. After Nicaragua filed the claim with the ICJ both countries built up troops along their land border and sent vessels to the disputed waters, although they later agreed to establish a zone of military exclusion pending the court's decision.