"The United States and Mexico have a close and complex bilateral relationship, with extensive economic linkages as neighbors and partners under the North American Free Trade Agreement (NAFTA). Bilateral relations are generally friendly, although the U.S. enactment of border fence legislation in 2006 caused some tension in the relationship. Drug trafficking issues are prominent in relations since Mexico is the leading transit country for cocaine, a leading supplier of methamphetamine and heroin, and the leading foreign supplier of marijuana to the United States. In October 2007, the United States and Mexico announced the Mérida Initiative to combat drug trafficking, gangs, and organized crime in Mexico and Central America. The Administration requested $500 million in FY2008 supplemental assistance for Mexico as part of a $1.4 billion, multi-year aid package for the Initiative. In final legislative action in late June 2008 on H.R. 2642 (P.L. 110-252), Congress appropriated $400 million for Mexico -- $352 million in FY2008 supplemental assistance and $48 million in FY2009 bridge fund supplemental assistance. In other action, on June 10, 2008, the House approved H.R. 6028 that would authorize $1.1 billion for Mexico over three years under the Mérida Initiative."