Tinmore always says Israel was the instigator and started the war by attacking first. These US State Depatrment reports say the fighting had been going on
before the Declaration of Independence. Let the document clear things up.
The United Nations resolution sparked conflict between Jewish and Arab groups within Palestine. Fighting began with attacks by irregular bands of Palestinian Arabs attached to local units of the Arab Liberation Army composed of volunteers from Palestine and neighboring Arab countries. These groups launched their attacks against Jewish cities, settlements, and armed forces. The Jewish forces were composed of the Haganah, the underground militia of the Jewish community in Palestine, and two small irregular groups, the Irgun, and LEHI. The goal of the Arabs was initially to block the Partition Resolution and to prevent the establishment of the Jewish state. The Jews, on the other hand, hoped to gain control over the territory allotted to them under the Partition Plan.
After Israel declared its independence on May 14, 1948, the fighting intensified with other Arab forces joining the Palestinian Arabs in attacking territory in the former Palestinian mandate. On the eve of May 14, the Arabs launched an air attack on Tel Aviv, which the Israelis resisted. This action was followed by the invasion of the former Palestinian mandate by Arab armies from Lebanon, Syria, Iraq, and Egypt. Saudi Arabia sent a formation that fought under the Egyptian command. British trained forces from Transjordan eventually intervened in the conflict, but only in areas that had been designated as part of the Arab state under the United Nations Partition Plan and the corpus separatum of Jerusalem. After tense early fighting, Israeli forces, now under joint command, were able to gain the offensive.
The Arab-Israeli War of 1948 - 1945?1952 - Milestones - Office of the Historian