Nikah mut'ah nikāḥ al-mutʿah, literally "pleasure marriage"; temporary marriage or Sigheh (صیغه ، ازدواج موقت) is a private and verbal temporary marriage contract that is practiced in Twelver Shia Islam in which the duration of the marriage and the mahr must be specified and agreed upon in advance. It is a private contract made in a verbal or written format. A declaration of the intent to marry and an acceptance of the terms are required as in other forms of marriage in Islam. According to Shia Muslims, Muhammad sanctioned nikah mut'ah (fixed-term marriage, called muta'a in Iraq and sigheh in Iran), which has instead been used as a legitimizing cover for sex workers in a culture where prostitution is otherwise forbidden. Some Western writers have argued that mut'ah approximates prostitution. Some sources say the Nikah mut'ah has no prescribed minimum or maximum duration, but others, such as The Oxford Dictionary of Islam, indicate the minimum duration of the marriage is debatable and durations of at least three days, three months or one year have been suggested. Some Muslims and Western scholars have stated that both Nikah mut'ah and Nikah misyar are Islamically void attempts to religiously sanction prostitution which is otherwise forbidden. The Zaidi Shia reject Mutah marriage. Historically there were many types of marriages, used for various purposes, as opposed to a full marriage; in mut'ah some of the rights of the husband and wife are non-existent. This was primarily used by those who could not stay at home with their wife and traveled a lot. For example, a traveling merchant might arrive at a town and stay for a few months, in that period he may marry a divorced widow, and they would take care of each other. When he has to leave to the next down, the marriage is over, and he might sign a mut'ah contract at his next place. Although in modern times such a thing is considered obsolete, due to the availability of fast travel, and primarily exists in Iran and Shia regions for sexual pleasure reasons as a means of Halal dating.