The United Nations said on Saturday that donors must honour pledges of more than $4.5 billion in aid for Sudan or endanger a January agreement ending Africa's longest civil war in the south of the country. Speaking after southern rebel leader John Garang took the oath of office as first vice president in a peace government, the U.N. Secretary-General said he would be writing to major donor countries to remind them of the urgent needs in Sudan, Reuters reported. "We do need support. We do need resources," Annan said, a day after he attended a meeting of the world's eight richest countries in Scotland. "We have got less than half of that we require and it would be a shame that having worked so hard for peace that it does fall apart for lack of cash." "Yesterday at the G8 (Group of Eight) I did raise this issue -- the need for support, the need to honour the pledges for Sudan and I will be writing to the major donors to urge them to convey their pledges into action," he added. n April donors pledged about $4.5 billion over the next few years, but most have yet to deliver on the promises. Major powers such as the United States have made it clear their priority is to work with the new government to implement the southern peace deal.