The White House on Tuesday cleared the way for up to 26 million dollars in aid to respond to the humanitarian crisis caused by fighting along the border between Sudan and South Sudan, dpa reported. President Barack Obama authorized the emergency funds for United Nations aid workers to care for the "unexpected and urgent needs" of more than 140,000 refugees who have fled South Kordofan and Blue Nile states, National Security Council spokesman Tommy Vietor said. "The United States is gravely concerned by the situation in South Kordofan and Blue Nile, especially as the violent clashes continue along the shared border with South Sudan," Vietor said. He called on Sudan and South Sudan to resolve outstanding issues, including nationality and border issues and oil revenue sharing.