KUALA LUMPUR (Reuters) - Malaysia should ban child marriage immediately, a United Nations human rights expert said on Monday, stepping into a controversy that has raged since reports in July that a 44-year-old Malaysian man had married an 11-year-old Thai girl.

Prime Minister of Malaysia Mahathir bin Mohamad addresses the 73rd session of the United Nations General Assembly at U.N. headquarters in New York, U.S., September 28, 2018. REUTERS/Shannon Stapleton

Prime Minister Mahathir Mohamad’s government, in power since May, has promised to raise the legal age of marriage to 18, provoking a backlash from some conservative Islamic leaders who argue that early marriage provides an answer to social ills like premarital sex and pregnancies out of wedlock.

Maud de Boer-Buquicchio, the U.N. special rapporteur on the sale and sexual exploitation of children, urged Malaysian authorities to protect the rights of minors, particularly young girls.

Married underage girls were at higher risk of domestic violence, and are often denied the chance to pursue an education, she told reporters.

“By marrying them, you are denying these girls their basic human rights,” said de Boer-Buquicchio, who was on an eight-day visit to mostly-Muslim Malaysia.

In Malaysia, the legal minimum age for marriage under civil law for both genders is 18. However, girls can marry at 16 with the permission of their state’s chief minister, while Islamic law sets a 16-year minimum age for girls and allows even earlier marriages with the permission of the sharia court.

The U.N. official called on Malaysia to remove exemptions that allowed underage children to marry, saying “there can be no exceptions.”

More than 5,000 applications for marriages involving minors were made at the sharia court between 2013 and 2017, government statistics show.

But many child marriages remained unreported, particularly among indigenous groups on Borneo, in Malaysia’s east, de Boer-Buquicchio said.

“It is time to be firm,” she said, adding that Malaysia’s government should engage religious and customary leaders on the issue.

“The political will is there, but the question is how you can reach out to all the different entities.”

Last year, Malaysia passed a law on sexual offences against children but did not criminalize child marriage.