"Mauritania is one of those few countries in which slavery still exists, in which slavery is still practiced. The government seems to deny it, at the same time there is an Anti-Slavery Act," Cornelis Flinterman, a Dutch member on U.N. Human Rights Committee told a news briefing.
"But it's very difficult for those who are held as slaves to bring complaints. Criminal cases do not seem to take place."
The most common is chattel slavery, meaning that slave status is passed down through generations, the slavery index said.
The U.N. committee of 18 independent experts works to uphold compliance with an international treaty on civil and political rights that bans slavery, servitude and forced labor. Mauritania is among 167 states to have ratified the pact.
It called on Mauritania, which straddles black and Arab Africa, to guarantee the legislation was applied effectively and to give victims sufficient recourse.