Guyana told the United Nations’ highest court on Monday that 70% of its territory is at stake in a historic border dispute with Venezuela over a swath of jungle that is rich in resources. The International Court of Justice is holding a week of hearings between the South American neighbors claiming ownership of the Essequibo region, which is rich in gold, diamonds, timber and other natural resources and is located close to massive offshore oil deposits. “This has been a blight on our existence as a sovereign state from the very beginning,” Guyana Foreign Minister Hugh Hilton Todd told judges at the Great Hall of Justice in The Hague. An 1899 decision by arbitrators from Britain, Russia and the United States drew the border along the Essequibo River largely in favor of Guyana. The U.S. represented Venezuela in part because the Venezuelan government had broken off diplomatic relations with Britain. Venezuela contends the Americans and Europeans conspired to cheat their country out of the land.…