The legality of cannabis varies from country to country. Possession of cannabis is illegal in most countries and has been since the beginning of widespread cannabis prohibition in the late 1930s. However, possession of the drug in small quantities has been decriminalized in many countries and sub-national entities in several parts of the world. Furthermore, possession is legal or effectively legal in the Netherlands, Uruguay, and in the US states of Colorado (Colorado Amendment 64), Oregon (Oregon Ballot Measure 91 (2014)), Alaska and Washington (Washington Initiative 502) as the federal government has indicated that it will not attempt to block enactment of legalization in those states. The federal district of Washington D.C. legalized cannabis for possession and use in 2015, but was blocked by a Congressional rider from instituting commercial sales and taxation. Cannabis is also legal in some U.S cities such as Portland and South Portland, both of which are in Maine. The United States Department of Justice is allowing all recognized Native American Reservations to regulate the legalization of cannabis, and the laws are allowed to be different from Federal and state law. On 10 December 2013, Uruguay became the first nation in the world to legalize the sale, cultivation, and distribution of cannabis.