The Benelux Union, also known as simply Benelux, is a politico-economic union and formal international intergovernmental cooperation of three neighbouring states in western Europe: Belgium, the Netherlands, and Luxembourg. The name Benelux is a portmanteau formed from joining the first few letters of each country's name – Belgium, Netherlands, Luxembourg – and was first used to name the customs agreement that initiated the union. It is now used more generally to refer to the geographic, economic, and cultural grouping of the three countries.