GAZA (Reuters) - Palestinian security forces announced practical steps to implement a cease-fire promised by President Yasser Arafat (news - web sites) after a suicide bombing in Tel Aviv raised the specter of strong Israeli retaliation.

But it was unclear on Sunday if a wide array of Palestinian factions in the West Bank and Gaza Strip (news - web sites) would lay down their arms after eight months of fighting against Israel.

Senior Palestinian officials said security chiefs in Arafat's Palestinian Authority (news - web sites) had met on Saturday and ordered their forces to take ``practical, direct, urgent and immediate'' action to put the cease-fire into effect.

There was no immediate Israeli reaction to the announcement, which did not meet a key Israeli demand -- the arrest by Arafat's forces of Muslim militants behind attacks that have rocked the Jewish state.

Israeli Prime Minister Ariel Sharon (news - web sites) planned to hold security consultations early on Sunday before the weekly meeting of his full cabinet.

After a security cabinet meeting on Saturday, Israeli officials said Arafat only had a few hours to make good on his cease-fire promise before possible Israeli military action.

``A decision was taken tonight and joint patrols, made up of all Palestinian security agencies, were set up to monitor and patrol the points of friction, to implement the decision in accordance with the higher national interest of the Palestinian people,'' a top security official in Gaza told Reuters.

Secretary of State Colin Powell (news - web sites) had been in touch with Arafat and Sharon earlier in day on ways to ease tensions following the suicide bombing that killed 19 people and wounded more than 90 in Tel Aviv on Friday, officials from both sides said.

ISRAEL SKEPTICAL OF ARAFAT'S PROMISE

At a news conference in the West Bank city of Ramallah, Arafat said he would do his utmost to achieve a cease-fire, a key recommendation by a U.S.-led committee that looked into ways to end the violence and return to peacemaking.

Israeli officials had said they were skeptical Arafat would take concrete steps to back up his promises and fend off a military reprisal for the Tel Aviv blast, the deadliest attack in Israel since the Palestinian uprising began in September.

``We exerted and we will now exert our utmost efforts to stop the bloodshed of our people and the Israeli people and to do all that is needed to achieve an immediate and unconditional, real and effective cease-fire,'' Arafat said.

Ahmed Helles, secretary general of Arafat's Fatah (news - web sites) faction in the Gaza Strip, said the movement ``was aware of the international pressure on the Palestinian Authority'' to stop the blood-letting.

He told Reuters that Palestinian factions, including Islamic groups opposed to any compromise with Israel, would meet on Sunday to discuss the cease-fire decision.

But Marwan Barghouthi, a prominent Fatah official in the West Bank, vowed: ``The Intifada (uprising) and resistance will continue as long as one Jewish settler and one Israeli soldier remains on our occupied land.''

Palestinians evacuated public buildings in the West Bank city of Nablus, fearing an air strike, and witnesses said many U.N. staff based in Gaza packed hurriedly and left for Israel.

Fatah declared a state of alert for possible Israeli attacks.

HORROR OVER SUICIDE BOMBING

World leaders reacted with horror to the explosion that tore through a group of youngsters outside a beachfront nightclub frequented by Russian-speaking immigrants, and urged both Israelis and Palestinians to show restraint.

Visiting German Foreign Minister Joschka Fischer went to the scene of the blast and stood with head bowed. ``The terror must be stopped,'' he said, before traveling to the West Bank for a meeting with Arafat.

At least 450 Palestinians, 108 Israelis and 13 Israeli Arabs killed since the Palestinian uprising erupted after peace talks stalled.

There was no public claim of responsibility for the bombing by any group.

A communique issued after the Israeli security cabinet meeting, held in a departure from procedure on the Jewish Sabbath, said Israel ``would do whatever is necessary to protect its citizens.''

But it gave no hint of what concrete action it might take.

Political sources said, however, that initial steps included tightening the blockades of the West Bank and Gaza, closing international crossings from Palestinian areas to Jordan and Egypt and closing Gaza's seaport and airport.

The Israeli army said it was barring Palestinians from traveling between cities within the West Bank on Saturday.

Of the Tel Aviv bombing, Arafat said: ``I repeat our condemnation of this tragic operation against civilians and of all operations that result in the killing of civilians, Palestinian or Israeli.''

Funerals for the victims were to be held on Sunday.
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PHOTO CAPTION

Palestinian President Yasser Arafat talks to reporters during his news conference with German Foreign Minister Joschka Fischer after they met at Arafat's office in Ramallah June 2, 2001. The Palestinians announced moves to implement a cease-fire promised by Arafat in the face of possible Israeli retaliation for a suicide bombing that killed 19 people. (Osama Silwadi/Reuters)
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