Iran's hard-line interior minister is encouraging temporary marriages as a way to avoid extramarital sex, a stance many in this conservative country fear would instead encourage prostitution.

A temporary marriage, or "sigheh," refers to a Shiite Muslim tradition under which a man and a woman sign a contract that allows them to be "married" for any length of time, even a few hours. An exchange of money, as a sort of dowry, is often involved.

Although the practice exists, it's not very common in Iran, a Shiite majority nation where many consider it a license for prostitution. Others, however, have advocated institutionalizing the tradition, saying it would help fight "illicit" sex in a country where sexual relations outside marriage are banned under Islamic law.

"Temporary marriage is God's rule. We must aggressively encourage that," state-run television quoted Interior Minister Mostafa Pourmohammadi as saying.

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The minister, who made his comments Thursday, was the first Iranian official to support the disputed practice in more than a decade. Former Iranian President Hashemi Rafsanjani raised the issue in the early 1990s but was opposed by the country's hard-line clerics.

"We have to find a solution to meet the sexual desire of the youth who have no possibility of marriage," Pourmohammadi was quoted as saying by local newspapers.

Half of Iran's population of 70 million is under 30. Taxi driver Reza Sarabi, 23, expressed the frustration of many young Iranian men who can't afford to buy a house and get married.

"I have no money to set up a matrimonial life. I don't want prostitutes. What should I do with my sexual needs?" he said.

The "sigheh" is banned in Sunni Islam, but similar practices can be found in Sunni countries. One such practice is the "urfi" marriage, an unofficial arrangement that is often kept secret. Although an urfi marriage involves signing a document in front of witnesses, the marriage can be broken by destroying the paper.

In Iran, temporary marriage has been reported as a way some widows and poor women help support themselves. But critics of the practice believe such arrangements only exacerbate the country's prostitution problem and undermine Iran's values.

"It will damage the foundation of the family," said lawyer Nemat Ahmadi, who argues it gives wealthy men religious cover to have affairs. "This will only promote prostitution."

Prostitution was banned in Iran after the 1979 Islamic revolution but has increased in recent years. There are no official statistics available in Iran on the number of prostitutes, but unofficial figures published by some media outlets put the number at several hundred thousand.

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