Most African countries are boxed into a commodity trap that condemns them to poverty and indebtedness, a United Nations study said as it called for new international commodity initiatives to set the continent on a sustainable growth path. The UN Conference on Trade and Development (Unctad) said sub-Saharan Africa's dependence on commodities whose pirces are in long-term decline had impeded savings and investment, set back development and led to persistently high levels of debt.