President Bush says Middle East peace will require leadership on both sides. He is repeating his call to Israel to withdraw from Palestinian lands and to Arab leaders to take a stronger stand against terrorism.

The president's frustration was evident as he called reporters to his side during a trip to Knoxville, Tennessee.

In firm tones pointing with his right hand for emphasis he said both sides to the Middle East conflict must take action now.

"I meant what I said to the prime minister of Israel," President Bush said. "I expect there to be withdrawal without delay. And I also meant what I said to the Arab world. In order for there to be peace, nations must stand up, leaders must stand up and condemn terrorism and terrorist activity."

Mr. Bush spoke shortly after Secretary of State Colin Powell began talks in the Middle East, and hours after Prime Minister Ariel Sharon told the Israeli parliament he would speed up the military operation in the West Bank.

The president said Israelis and Arabs share a mutual responsibility to end the violence and create the conditions for peace.

"And it is going to require leadership on both sides," President Bush added. "The United States is firmly committed to achieving peace. And is firmly committed, I am firmly committed to what I expect from both parties."

Bush administration officials are constantly making those expectations clear in Middle East capitals. While Secretary Powell was in Morocco, the president's Middle East envoy Anthony Zinni was meeting with Ariel Sharon.

Speaking after talks with Morocco's King Mohammed, Secretary Powell demanded a clear statement from Israel that they are beginning to withdraw. General Zinni was expected to deliver the same message personally to Prime Minister Sharon.