KINSHASA, Congo: The United Nations Children's Fund says more than a quarter of Congolese children are not going to school, including 1.3 million in the mineral-rich Katanga province.

UNICEF says more than half of children start school late. It says three times more children are out of school in rural areas than urban.

The agency blamed, in part, low income and educational levels of some parents, early child marriage and child labor in agriculture and mining. But it also said children are being kept out of school by insufficient funding for education and not enough places at schools.

It quoted education minister Maker Mwangu promising that Congo's government will immediately invest $40 million in building schools.

UNICEF helped fund the study conducted by Burkina Faso's University of Ouagadougou and published Monday.