Israeli leaders on Sunday backed away from Prime Minister Ariel Sharon's (search) latest threats against Yasser Arafat (search), saying there are no immediate plans to kill the Palestinian leader.

Sharon declared in a television interview over the weekend that he is no longer bound by a promise to the United States not to harm Arafat.

The comments, which were criticized in Washington, Europe and the Arab world, raised speculation that Arafat might be in Israel's crosshairs. In recent weeks, Israel has killed the founder of the Hamas militant group and his successor.

After nightfall Sunday, Palestinian gunmen opened fire on a vehicle in the southern West Bank, killing one Israeli border policeman and wounding three others, rescue workers said. In another shooting attack nearby, an Israeli Arab was seriously wounded, rescue workers said.

Sharon accuses Arafat of supporting terrorism. Under U.S. pressure, however, he has refrained from attacking Arafat, instead confining him to a compound in the West Bank (search) town of Ramallah for more than two years.

Arafat greeted 400 Palestinian schoolchildren at his headquarters Sunday. The students chanted anti-Sharon slogans and called for an end to Israel's siege of the Palestinian leader.

Speaking to reporters afterward, Arafat said he is not afraid to die. "Our destiny is to be martyrs in this holy land," Arafat said.

Nonetheless, Palestinian officials said Arafat is taking the threats seriously.

"We see these threats as real, and Arafat himself realizes that," said Hani al-Hassan, a senior official in Arafat's Fatah movement. Hassan said the group had decided to boost security around Arafat but gave no details.

With Arafat's movements limited, there is little the Palestinians can do to protect him from Israel's air force. The Israeli air strikes that killed the two Hamas leaders in Gaza added to Palestinian concerns for Arafat.

However, Israeli Vice Premier Ehud Olmert and Cabinet minister Gideon Ezra said Sharon has no plans to expel or assassinate Arafat. They said the Israeli leader had merely repeated a long-standing Israeli position.

"The prime minister doesn't intend to carry out anything next week or today or tomorrow," Olmert, a Sharon confidant, told Army Radio.

Last September, Israel's Cabinet decided Arafat should be "removed" after a pair of homicide bombings killed 15 Israelis.

Sharon took the threats to a new level in a TV interview Friday, saying he had told President Bush that Israel is no longer bound to a pledge not to attack Arafat.

The remarks drew a quick rebuke from the White House, which stressed that Bush remains opposed to attempts to harm Arafat.

Moshe Katsav, Israel's ceremonial president, hinted that U.S. pressure could cause Sharon to backtrack.

"If the United States asks us not to liquidate Yasser Arafat, I assume that the government will honor that request," Katsav told Israel 's Channel Two TV.

Sharon's threats appeared to be aimed at winning support among hawkish party members for his plan to withdraw from the Gaza Strip and four West Bank settlements.

Sharon's Likud Party is holding a referendum on the plan on May 2, and polls show only a small advantage for those who favor it. Sharon says the withdrawal will improve Israel's security, but hard-line opponents accuse the prime minister of caving in to terrorism.

Sharon has recently backed off pledges to honor the referendum, saying he will present the plan to the Cabinet and parliament even if he loses the party vote.

"We will take the initiative and move forward with determination and courage," Sharon said in a speech marking Israel's Memorial Day, beginning Sunday evening.

Sharon met on Sunday with several influential Likud ministers, including Finance Minister Benjamin Netanyahu and Education Minister Limor Livnat, looking for help in building party support for his plan.

The two ministers, who have given lukewarm support to the plan, declined to take a more active role in promoting it, Army Radio reported.

In another development, police said Sunday they had arrested three Palestinians who carried out two shooting attacks in Jerusalem, including the fatal shooting last month of an Arab jogger. Claiming responsibility, a violent group apologized, saying the gunmen thought the target was a Jew. The second victim, a Jew, was seriously wounded.

A court ordered the suspects held for 12 days. The three were caught as they were preparing another attack, police said.