Palestinian leader Yasser Arafat forced the postponement Tuesday of a summit between the Israeli and Palestinian prime ministers over implementing a U.S.-backed Mideast peace plan, a senior Palestinian official said. Palestinian Prime Minister Mahmoud Abbas and Israel's Ariel Sharon had been scheduled to meet on Wednesday. But Arafat told the PLO executive committee in a meeting Tuesday that he wanted to discuss the latest Israeli proposals for security arrangements before approving another summit, the official said on condition of anonymity. The official, who is a member of the committee, said Arafat wanted to send a message that he - not Abbas - is in charge of negotiations with Israel. Israel has refused to deal with Arafat, charging that he is involved in terrorism. Officials in Sharon's office said no new summit date was set, but Israel Radio said it might take place Thursday. At the White House, spokesman Ari Fleischer said he "would not be surprised if a bilateral meeting still took place in the near future." Officials are arranging a three-way summit with President Bush, Sharon and Abbas early next month, possibly in Jordan. Israeli Foreign Minister Silvan Shalom said Tuesday that concrete results could be expected. Bush "would not bother coming all the way out here to leave without a decision of some kind," he told Israel TV. Jordan's information minister said Bush would hold a three-way summit as well as a separate meeting with Egypt and Jordan's leaders next week in Jordan. But the White House said Bush is still considering a number of possibilities. Sharon and Abbas, who took office in late April, met on May 17, the first Israeli-Palestinian summit meeting since the intifada erupted in September 2000. Sharon stunned both dovish opponents and hardline allies on Monday by declaring that Israel's occupation in the West Bank must end, stunning. That followed his government's conditional acceptance Sunday of the so-called "road map" to peace. **PHOTO CAPTION*** Palestinian leader Yasser Arafat speaks during a news conference with French Foreign Minister Dominique de Villepin, after their meeting in the West Bank city of Ramallah Monday May 26, 2003. ( AP Photo/Muhammed Muheisen)