The Mauritanian ouguiya (sign: UM;Arabic: أوقية‎; currency code: MRU), also spelled "ougiya",is the currency of Mauritania. Each ouguiya constitutes five khoums (singular and plural in English, Arabic: خمس‎, meaning "one fifth"). There are 100, 200, 500, 1000, 2000 banknotes in circulation. From January 1, 2018, a new version of ujiya will be issued. The material of the whole set of banknotes will be changed from paper to plastic. The ratio of new banknotes to old banknotes is 1:10.