Sudan has asked for US help in ending South Sudan’s support for rebels on Khartoum’s territory, official media said before a Thursday UN deadline for the two Sudans to make peace.Foreign Minister Ali Karti made the request when US Secretary of State Hillary Clinton, who is on an African tour, telephoned him on Wednesday, the SUNA news agency reported."He affirmed that the problem between Sudan and South Sudan is a security one in the first place,” with South Sudan backing rebels opposed to the Khartoum regime, SUNA said."He said that a final agreement could not be achieved under the absence of security, calling on the American official to urge South Sudan... to cut its relations” with forces in South Kordofan and Blue Nile states and to halt its support for rebels in the Darfur region, it added.Clinton on Wednesday began her 11-day Africa mission in Senegal. She heads on Thursday to Uganda, on her way to South Sudan which became independent in July last year following a 2005 peace deal that ended a 22-year civil war.The United States played a major part in South Sudan’s birth but has maintained sanctions against Khartoum since 1997 over human rights and other concerns.Sudan accuses South Sudan of supporting insurgents from the Sudan People’s Liberation Movement-North (SPLM-N), a charge which analysts believe despite denials by the government in Juba.The SPLM-N has been fighting in South Kordofan and Blue Nile since June last year.South Sudan also denies supporting rebels from Sudan’s Darfur region but suspected fighters from Darfur’s Justice and Equality Movement (JEM) were seen alongside Southern troops during border fighting between Sudan and South Sudan in April.The UN Security Council ordered a ceasefire between the two Sudans under a May resolution that gave them until this Thursday to settle critical issues left unresolved at the South’s independence.These include oil fees, the disputed border, the status of nationals of one country in another, and the contested Abyei region.The UN also told both sides to stop supporting each other’s rebels.