Israel and Sudan do not have official bilateral relations.
Israel–Sudan relations Wikipedia
Sudan went officially to war with Israel in the 1948 Arab–Israeli War and the Six-Day War in 1967 though it did not participate in either the Suez Crisis, having only gained its independence earlier that year. In the early 1950s, Sudan – then still not independent – had active trade relations with Israel.
Sudan also did not actively participate in the Yom Kippur War, when Sudanese forces arrived too late to participate. Israel backed Christian militias that fought the Sudanese government in the First and Second Sudanese Civil Wars.
In January 2016, Sudanese Foreign Minister Ibrahim Ghandour floated normalized ties with Israel provided the U.S. government lifts economic sanctions. Sudanese President Omar al-Bashir followed that up by saying in an interview with Saudi newspaper Al-Okaz, "Even if Israel had conquered Syria, it would not have inflicted the destruction taking place there right now, would not have killed the number of people killed so far and would not have expelled people the way they are being expelled now.” According to Israeli Deputy Minister for Regional Cooperation Ayoob Kara, Sudan and Israel do maintain relations covertly. It was revealed in early September 2016 that Israel had contacted the U.S. government and other Western countries and encouraged them to take steps to improve relations with Sudan in wake of the break in relations between the Arab-African country and Iran in the past year, all but confirming a secret alliance between Sudan and Israel. Kara later revealed at an event in Beersheba that he was maintaining contacts with many Sudanese officials and did not deny that a Sudanese official recently visited Israel.