The rebel Justice and Equality Movement became the seventh militia in Darfur to prohibit the use of child soldiers. JEM made the decision following recent negotiations with members of the hybrid U.N.-African Union Mission in Darfur.
UNAMID chief Aichatou Mindaoudou said she welcomed the step by what's considered one of the largest armed groups in Darfur.
"Child soldiering is detrimental to peace and to children, who are the future of Darfur," she said in a statement. "(UNAMID) applauds JEM's commitment toward protecting children and appeals to all members of armed groups and forces to do the same."
The U.S. State Department last week advised U.S. citizens to avoid traveling to Darfur or the Sudanese states of Blue Nile and South Kordofan.
The warning said that although the government in Khartoum has taken steps to control the violence, armed groups in the region have threatened to attack Western interests. The State Department said the threat level in Sudan, particularly in Darfur, "remains critical."