Watching on TV Tuesday as Palestinian Authority President Mahmoud Abbas appealed for peace with Israel at the beginning of a Middle East conference in the United States, a Hamas spokesman in Gaza rejected his call and said Abbas speaks only for himself. The spokesman, Fawzi Barhoum, watched the opening speeches at his office in Gaza City. He said Abbas "has no mandate to discuss, to agree, or to erase any word related to our rights." Barhoum said Abbas went to the conference "without any support from his people. He is isolated (and) represents himself only." Barhoum expressed disappointment in the participation of Arab nations in the summit. Their presence is seen as support for renewed peace negotiations between Israel and the Palestinians. Instead, Barhoum indicated that Hamas would continue its violence against Israel. "We will use all the tools of resistance to achieve our rights," he said.