from the urban upper and middle classes in Haifa, Jaffa and Jerusalem, or Jewish-dominated areas, evacuated abroad or to Arab centres eastwards. This situation caused the United States to withdraw its support for the Partition Plan, thus encouraging the Arab League to believe that the Palestinian Arabs, reinforced by the Arab Liberation Army, could put an end to the plan. The British, on the other hand, decided on 7 February 1948 to support the annexation of the Arab part of Palestine by Transjordan. Although a certain level of doubt took hold among Yishuv supporters, their apparent defeats were due more to their wait-and-see policy than to weakness. David Ben-Gurion reorganised Haganah and made conscription obligatory. Every Jewish man and woman in the country had to receive military training. Thanks to funds raised by Golda Meir from sympathisers in the United States, and Stalin's decision to support the Zionist cause, the Jewish representatives of Palestine were able to sign very important armament contracts in the East. Other Haganah agents recuperated stockpiles from the Second World War, which helped improve the army's equipment and logistics. Operation Balak allowed arms and other equipment to be transported for the first time by the end of March. Ben-Gurion invested Yigael Yadin with the responsibility to come up with a plan of offence whose timing was related to the foreseeable evacuation of British forces. This strategy, called Plan Dalet, was readied by March and implemented towards the end of April. A separate plan, Operation Nachshon, was devised to lift the siege of Jerusalem. 1500 men from Haganah's Givati brigade and Palmach's Harel brigade conducted sorties to free up the route to the city between 5 and 20 April. Both sides acted offensively in defiance of the Partition Plan, which foresaw Jerusalem as a corpus separatum, under neither Jewish nor Arab jurisdiction. The Arabs did not accept the Plan, while the Jews were determined to oppose the internationalisation of the city, and secure it as part of the Jewish state. The operation was successful, and enough foodstuffs to last two months were trucked into Jerusalem for distribution to the Jewish population. The success of the operation was assisted by the death of al-Husayni in combat. During this time, and independently of Haganah or the framework of Plan Dalet, irregular fighters from Irgun and Lehi formations massacred a substantial number of Arabs at Deir Yassin, an event that,