CAIRO – An 8-year-old Saudi girl has divorced her middle-aged husband after her father forced her to marry him last year in exchange for about $13,000, her lawyer said Thursday.

Saudi Arabia has come under increasing criticism at home and abroad for permitting child marriages. The United States, a close ally of the conservative Muslim kingdom, has called child marriage a "clear and unacceptable" violation of human rights.

The girl was allowed to divorce the 50-year-old man who she married in August after an out-of-court settlement had been reached in the case, said her lawyer, Abdulla al-Jeteli. The exact date of the divorce was not immediately known.

A court in the central Oneiza region previously rejected a request by the girl's mother for a divorce and ruled that the girl would have to wait until she reached puberty to file a petition then.

There are no laws in Saudi Arabia defining the minimum age for marriage. Though a woman's consent is legally required, some marriage officials don't seek it.

But there has been a push by Saudi human rights groups to define the age of marriage and put an end to the phenomenon.

One Saudi human rights activist Sohaila Zain al-Abdeen was optimistic that the girl's divorce would help efforts to get a law passed enforcing a minimum marriage age of 18.

"Unfortunately, some fathers trade their daughters," she told The Associated Press. "They are weak people who are sometimes in need of money and forget their roles as parents."

It was not clear if the man received money for the divorce settlement. The man had given the girl's father 50,000 riyals, or about $13,350, as a marriage gift in return for his daughter, the lawyer said.

The 8-year-old girl's marriage was not the only one in the kingdom to receive attention in recent months. Saudi newspapers have highlighted several cases in which young girls were married off to much older men or young boys including a 15-year-old girl whose father, a death-row inmate, married her off to a cell mate.

Saudi Arabia's conservative Muslim clergy have opposed the drive to end child marriages. In January, the kingdom's most senior cleric said it was permissible for 10-year-old girls to marry and those who believe they are too young are doing the girls an injustice.

But some in the government appear to support the movement to set a minimum age for marriage. The kingdom's new justice minister was quoted in mid-April as saying the government was doing a study on underage marriage that would include regulations.

There are no statistics to show how many marriages involving children are performed in Saudi Arabia every year. Activists say the girls are given away in return for hefty marriage gifts or as a result of long-standing custom in which a father promises his infant daughters and sons to cousins out of a belief that marriage will protect them from illicit relationships.