Operation Assaf (Hebrew: מִבְצָע אָסָף, Mivtza Asaf) was an Israel Defense Forces (IDF) operation against the Egyptian Army between December 5–December 7, 1948, during the 1948 Arab-Israeli War. The successful operation's aim was to take control of the western Negev Desert. It was a small operation, executed between two larger operations in that theatre, Operation Yoav and Operation Horev.
Following Operation Yoav, the Egyptian Army tried to stabilize a defensive line between its two arms of controlled territory in the Negev, along the Beer Sheva-Gaza road. With international peace-efforts intensifying, both sides felt that the war was drawing to a close, and such a strong defensive line would help Egypt claim the majority of western and southern Negev, which included some Israeli settlements.
Israel wished to disconnect the two Egyptian arms before it could construct and man strong fortifications along the new defense line. So, Operation Assaf was planned and carried out starting December 5, just two weeks after Operation Yoav ended. In order to surprise the defenders, IDF units were transported via the newly captured Beer Sheva to the Egyptian Army's southern (rear) flank, and attacked northwards (the Egyptians expected attacks from the north and east).
The operation was carried out mainly with the Golani Brigade's Gideon Battalion infantry forces, for whom this was the first operation in southern Israel or in flat desert terrain (Golani was normally stationed in the lush and hilly Upper Galilee region, near the Golan Heights for which it is named). In addition, the assault battalion and several armoured personnel carriers from the armored battalion, both of the 8th Armored Brigade, participated in combat. A few artillery and mortar batteries assisted them.