Kathmandu. The United Nations has warned on Friday that more than 7 million people need food aid in conflict-torn South Sudan.The United Nations World Food Program has condemned the situation in the world's 'youngest' sovereign nation as 'dangerous' and said the organization is in a 'tough struggle against time' to scale up its response.WFP's 'Country Director' for South Sudan, Mutinta Chimuka, told journalists in Geneva via video link from Bor city in South Sudan's Jonglei state,