The exile of the sultan did not alleviate French difficulties in Morocco, and an insurgency broke out which targeted both the regime and its collaborators with boycott campaigns as well as acts of violence. Several assassination attempts were made against the new puppet sultan, Mohammed Ben 'Arafa, and one of the boycott campaigns was aimed at the country's mosques due to prayers being said in the new sultan's name. Eventually, with the decolonialization process under way in Tunisia and the independence war in Algeria, the French agreed to negotiate Morocco's independence at a conference on August 23, 1955. By October 1 Mohammed Ben 'Arafa had abdicated and later that month even Thami el-Glaoui supported Mohammed V's return. The sultan returned landed at Rabat-Salé Airport at 11:42 am on November 16, greeted by cheering crowds. The French-Moroccan Declaration of Independence was formally signed on March 2, 1956, and Tangier was reintegrated to Morocco later that year. In 1957 Mohammed V adopted the official title of "King", which has since been used by his successors, Hassan II and Mohammed VI.