Gambian lawmakers have passed a bill criminalising female circumcision and introducing prison terms of up to three years for anyone flouting the ban.
The National Assembly voted by a large majority to write the ban into the criminal code late Monday, a month after President Yahya Jammeh branded the practice outdated and ordered its immediate cessation.
Vice-President Isatou Njie Saidy told legislators the new law would "enforce the constitutional rights of women and girls not to be subjected to practices that are harmful to their health and well-being".
Female genital mutilation, or FGM, remains highly common in the Gambia, along with a number of other African countries and parts of the Middle East.
The World Health Organization estimates that more than 125 million women worldwide have undergone the practice, which involves cutting off the labia and clitoris, often when girls are young.
It can lead to serious health problems, including infections, bleeding, infertility and complications in childbirth, and impairs sexual pleasure.
Jammeh declared in November that the practice was not required by Islam -- the religion of around 95 percent of the country's 1.8 million population -- and that it should be banished to the past, according to a government spokesman.
Jammeh earlier this month declared the Gambia an Islamic state.
Before Monday's vote there was no specific legislation and prosecutions would have had to rely on existing aspects of the penal code, such as previsions dealing with grievous bodily harm.
The Women Amendment Act 2015 mandates a jail term of up to three years, a fine of $1,300 or both for anyone caught practising or involved in the organisation of FGM.
Samba Bah, the assembly's minority leader, voted against the bill, voicing concerns that the government had not sufficiently consulted with the public over what had previously been considered a rite of passage in the Gambia.
But deputy speaker Fatou Mbye hailed one of the "most progressive" pieces of legislation the parliament had ever passed.
According to UN children's fund Unicef, around three quarters of Gambian women are living with the effects of genital mutilation.
A former British colony nestled within Senegal, the country is one of the poorest in the world and has been ruled with an iron fist by Jammeh since he seized power in a coup in 1994.