The U.N. Security Council on Tuesday called on Sudan and rebels in areas bordering South Sudan to grant immediate access for U.N. aid workers to the turbulent region, expressing "deep and growing alarm” at rising hunger levels.Fighting has been raging for months between the Sudanese army and rebels from the SPLM-North, which wants to topple the Khartoum government, in the states of South Kordofan and Blue Nile, adjacent to newly independent South Sudan.In a statement, the 15-nation council expressed "deep and growing alarm with the rising levels of malnutrition and food insecurity” in parts of the two states, "which could reach emergency levels if not immediately addressed.”It called on Sudan’s government and the rebels to allow immediate access to U.N. personnel to allow them to carry out a needs assessment and deliver supplies and equipment to civilians affected by the conflict.The United States issued a similar call last month, but Sudan said it would continue to allow only limited access to U.N. agencies and aid groups. The Foreign Ministry said relief would have to be channeled through an official humanitarian aid commission and the Sudanese Red Crescent.U.N. agencies and aid groups have been able to keep only small teams of local staff on the ground since the conflict erupted. The government, citing security risks, has stopped aid workers from visiting areas where there has been fighting.The Security Council also called on Khartoum and the SPLM-North to immediately stop fighting and to return to talks to resolve their conflict.South Kordofan and Blue Nile are home to tens of thousands of fighters who battled Khartoum as part of the southern army during a civil war that ended in 2005. Khartoum accuses Juba of continuing to back the insurgents, which South Sudan denies.The fighting in recent months has forced about 417,000 people to flee their homes, more than 80,000 of them to South Sudan, according to the United Nations.In the latest military action, Sudan’s armed forces said on Saturday they had seized an area held by rebels after a battle lasting two days in Blue Nile.