Outgoing Labor Party chairman Shimon Peres called Amir Peretz, the winner of Labor's leadership, Friday morning to congratulate him on his victory. Peres refrained from calling the newly elected chairman since the results were announced early Thursday morning. In the phone call he promised to do everything in his power to help Peretz succeed in his position, Israel Radio reported. The new chairman, who noted Thursday that Peres was the only Labor leader who didn't call him, told his predecessor that he was waiting for the call. He claimed this was the most important phone call of all the congratulators.