Afer months of turmoil, the longtime president of the New York-based World Jewish Congress, Edgar Bronfman, announced his resignation Monday in a move meant to avert an historic split in the organization, officials said. Bronfman, 77, led the WJC for the last quarter century. The decision was announced at a meeting of the group's steering committee in Manhattan. A new president will be elected on June 10. Pierre Besnainou, president of the European Jewish Congress, had been calling for new leadership, saying he might pull out of the organization if elections were not held this year. Besnainou said Monday he would back Mendel Kaplan, chairman of the executive, for WJC president. It was not known late Monday whether Jewish National Fund president Ronald S. Lauder would enter the race. Bronfman's son, Matthew, is not expected to be a candidate. Bronfman's resignation came less than two months after he ousted WJC chairman Israel Singer over allegations of financial improprieties. Bronfman's decision followed months of infighting over control of the WJC's Jerusalem office. That dispute stemmed from the appointment of Israeli Ambassador to the European Union Oded Eran to head the office. The appointment was seen by members of the Israeli board as an attempt by the organization's New York-based secretary-general, Stephen E. Herbits, to bypass the Jerusalem office with a hand-picked appointment who would serve as Bronfman's personal emissary. Herbits on Monday apologized to the Tunisian-born President of the European Jewish Congress for likening him to an Arab in an internal memo, Besnainou said. The memo was first published in The Jerusalem Post on Friday. A WJC spokesman had previously denied that Herbits had made an ethnic slur. The elder Bronfman has served as president of the organization since 1979. The nonprofit organization is best known for compelling European banks to pay hundreds of millions of dollars in Holocaust restitution.