Kampala - The head of the International Committee of the Red Cross warned on Monday that South Sudan's inability to pay civil servants risked worsening a humanitarian crisis and urged donors to step in.ICRC chief Peter Maurer was in Kampala after a three-day visit to conflict-torn South Sudan, where he warned of a "spiral which no international actor can prevent" as civil servants working in critical sectors such as health and water services go unpaid.Maurer said he had "rarely seen another conflict in the world where the fighting and the economic fragility - the inability of the state to pay salaries - has had so much humanitarian impact."He called for the international community and national actors "to use every resource possible to finance the salaries of those who are working in critical infrastructures."South Sudan's civil war erupted in December 2013 just two years after it obtained independence from Sudan, when President Salva Kiir accused his former deputy Riek Machar of plotting a coup.Thousands have been killed and some four million displaced, according to UN figures, and Maurer warned the situation could get worse if South Sudan's economic crisis was not halted.Inflation in the country has reached record levels, increasing by 730% in the 12 months up to August 2016, according to World Bank figures.The government has struggled to pay civil servants, some for several months."This is not a crisis which can be reduced to the conflict, this is also a crisis where the uncomfortable elements of poverty, of lack of development, of international pressures on the economy pay an enormous toll," said Maurer.He was set to meet with Ugandan president Yoweri Museveni, who has resisted calls from many in the international community to support an arms embargo on South Sudan. Uganda is also host to one million refugees from South Sudan.