NAIROBI, May 31 (Reuters) - The United Nations World Food Programme (WFP) said on Thursday it would resume operations in the drought-affected Karamoja region of northern Uganda following government assurances on the security of staff. The U.N. agency suspended food deliveries to half a million people struggling to cope with the effects of drought after a WFP driver was shot dead on Monday during an ambush by unidentified gunmen in Kotido District. "We must recognise that WFP works in a challenging environment," said Relief and Disaster minister Musa Ecweru in a joint statement with the U.N. humanitarian agency. "The government will provide full security to the staff and property of WFP and all humanitarian partners in the region to enable them to achieve their mission." WFP said it was compelled to resume its work in the troubled region due to the magnitude of the drought and the desperate need for relief assistance. Drought-prone Karamoja has suffered banditry and inter-clan warfare for decades, fuelled by disputes over shrinking water supplies and a flood of cheap, semi-automatic weapons trafficked from conflicts in the Horn of Africa.