evidence: Nicaragua lays claim to all the islands on its continental shelf, covering an area of over 50,000 km2 in the Caribbean Sea, including Bajo Nuevo Bank and all islands associated with the San Andrés and Providencia archipelagoes. It has persistently pursued this claim against Colombia in the International Court of Justice (ICJ), filing cases in both 2001 and 2007. The main cause of the dispute lies in the debated validity and applicability of the Esguerra-Bárcenas treaty, exchanged with Colombia in March 1928. The United States claim was made on 22 November 1869 by James W. Jennett under the provisions of the Guano Islands Act. Most claims made by the U.S. over the guano islands in this region were officially renounced in a treaty with Colombia, dated September 1972. But whether or not Bajo Nuevo Bank was included in the agreement is disputed, as the bank is not mentioned specifically by name within the treaty, and Article 7 of the treaty states that matters not specifically mentioned in the treaty are not subject to its terms. The U.S. administers the bank as an unorganized, unincorporated United States territory. Honduras, prior to its ratification of a maritime boundary treaty with Colombia on 20 December 1999, had previously also laid claim to Bajo Nuevo and nearby Serranilla Bank. Both states agreed upon a maritime demarcation in 1986 that excluded Honduras of any control over the banks or their surrounding waters. This bilateral treaty ensured that Honduras implicitly recognises Colombia's sovereignty over the disputed territories. Honduras' legal right to hand over these areas was disputed by Nicaragua before the ICJ.