Khartoum, July 10 (SUNA)- President of the Republic, Field Marshal Omer Al-Bashir, Sunday made telephone calls with the President of South Sudan State, Salva Kiir, and the First Vice - President of South Sudan, Dr. Riek Machar. President Al-Bashir has called on both Salva Kiir and Dr. Machar to stick to self-restraint and to elevate the interest of South Sudan people for the sake of guaranteeing stability at the region and not provide a chance for extremism. He stressed the necessity of avoiding blood-shed and dragging the area into tribal and political disputes that will hinder the peace and development process in South Sudan State.