The only varieties usually recognized as languages in their own right are Dungan and Taz. This is mostly due to political reasons as they are spoken in the former Soviet Union and are usually not written in Han characters but in Cyrillic. Dungan is in fact a variety of Mandarin, with high although asymmetric mutual intelligibility with Standard Mandarin. Various mixed languages, particularly those spoken by ethnic minorities, are also referred to as languages such as Tangwang, Wutun, and E. The Taiwanese Ministry of Education uses the terms "Minnan language" and "Taiwan Minnan language".