There were no mention of the borders of the new state other than that it was in Eretz Israel . An official cablegram from the Secretary-General of the League of Arab States to the UN Secretary-General on 15 May 1948 stated publicly that Arab Governments found " themselves compelled to intervene for the sole purpose of restoring peace and security and establishing law and order in Palestine " ( Clause 10 ( e ) ) . Further in Clause 10 ( e ) : " The Governments of the Arab States hereby confirm at this stage the view that had been repeatedly declared by them on previous occasions , such as the London Conference and before the United Nations mainly , the only fair and just solution to the problem of Palestine is the creation of United State of Palestine based upon the democratic principles ... " That day , the armies of Egypt , Lebanon , Syria , Jordan and Iraq invaded what had just ceased to be the British Mandate , marking the beginning of the 1948 Arab – Israeli War . The nascent Israeli Defense Force repulsed the Arab nations from part of the occupied territories , thus extending its borders beyond the original UNSCOP partition . By December 1948 , Israel controlled most of the portion of Mandate Palestine west of the Jordan River . The remainder of the Mandate consisted of Jordan , the area that came to be called the West Bank ( controlled by Jordan ) , and the Gaza Strip ( controlled by Egypt ) . Prior to and during this conflict , 713,000 Palestinian Arabs fled their original lands to become Palestinian refugees , in part due to a promise from Arab leaders that they would be able to return when the war had been won , and also in part due to attacks on Palestinian villages and towns by Israeli forces and Jewish militant groups . Many Palestinians fled from the areas that are now Israel as a response to massacres of Arab towns by militant Jewish organizations like the Irgun and the Lehi ( group ) ( See Deir Yassin massacre ) . The War came to an end with the signing of the 1949 Armistice Agreements between Israel and each of its Arab neighbours
Deir Yassin massacre
Deir Yassin massacre
Arab–Israeli conflict