Does touching a member of the opposite sex break wudu?

Although it is sinful for a man to touch a woman who is not his mahram, according to the Hanafi school, neither the man’s nor the woman’s wudu is invalidated in this situation. (Mevsılî, el-İhtiyâr, 1/10) According to the Shafi'i school, however, if a person touches a member of the opposite sex with whom marriage is permissible in Islam, and there is no barrier between them, the wudu of both is invalidated. (Mâverdî, el-Hâvî, 1/183-187) However, touching the hair or nails of the opposite sex does not break wudu.

Source: T.C. Diyanet İşleri Başkanlığı, Din İşleri Yüksek Kurulu