Arafat back in frame as the road map crumples

America has turned to Yasser Arafat - a man it has sought to marginalise and sideline for months - to help the so-called Middle East "road map" following the Jerusalem bus bombing and Israel's killing of a senior militant leader.

Months after the US demanded the Palestinians elect a Prime Minister in an effort to reduce the authority of Arafat, the US Secretary of State, Colin Powell, on Thursday asked him to help stop the cycle of violence. His appeal to the Palestinian Authority's chairman was an open admission of the influence and power Arafat still wields, whether Washington likes it or not, and the inability of Prime Minister Mahmoud Abbas to stop Palestinian attacks against Israeli targets.

"The end of the road map is a cliff that both sides will fall off," Powell said, speaking at the UN headquarters in New York.

"I call on Chairman Arafat to work with Prime Minister Abbas and to make available to Prime Minister Abbas those security elements that are under his control so that they can allow progress to be made on the road map - end terror, end this violence that just results in the further repetition of the cycle that we've seen so often."

He added: "The alternative is what? Just more death and destruction, let the terrorists win, let those who have no interest in a Palestinian state win, let those who have no interest but killing innocent people win? No. That is not an acceptable outcome. Both parties realise it and I think both sides should recommit themselves to finding a way forward."

Powell's appeal to Arafat - who for months has been all but confined to his Ramallah headquarters - followed the suicide bombing of a bus in Jerusalem in which 20 people were killed and scores injured.

Two militant groups, Hamas and Islamic Jihad, both claimed responsibility for the blast, which targeted ultra Orthodox Jews returning from the Western Wall. Six children were among those killed.

Israel - in what it said was a response to the bus bombing - assassinated senior Hamas political leader Ismail Abu Shanab in a missile attack.

Israeli troops also raided the West Bank towns of Nablus, Jenin and Tulkarem in search of militants while in Hebron, troops blew up the home of the bus bomber, a routine punishment intended as deterrent.

In turn, both Hamas and Islamic Jihad said they were calling off a truce which had been declared almost eight weeks ago and has reduced the level of Palestinian violence.

Tens of thousands of Hamas supporters filled the streets of Gaza City and threatened to avenge the killing of Abu Shanab, and one rally leader warned Israelis to prepare body bags for the dead.

"Today we are going to blow up the so-called ceasefire and to turn our words into bullets that will hit the Zionists in every corner in our occupied land," a speaker told the crowd.

The crowd responded to questions shouted over a loudspeaker: "What is your movement? Hamas! What is your choice? Resistance! ... What is your best wish? To die for the sake of God!"

Abu Shanab, 53, was a US-educated engineer and a prominent member of the Hamas political wing. He is the third political leader in the group to be killed in the past two years. Israel says he was involved in the planning of terror attacks.

Some marchers in the Gaza Strip said talks with Israel were no longer useful.

Powell has been America's most vocal supporter of the US-backed road map that calls for the creation of a separate Palestinian state as early as 2005, in exchange for a guarantee of peace.

Yesterday he also called on all countries, including Arab nations, "to step up now and insist that the terror perpetrated by organisations such as Hamas must come to an end". Although he did not name Syria, Powell has long called on Damascus to stop supporting Palestinian militant groups that the US believes operate from Syrian territory.

Apart from its impact on the Middle East itself, the effort to keep the road map on track is politically important to the Bush Administration as a way of trying to reassure the world that he is still interested in diplomacy despite what many observers may believe.

Adding to the powder-keg atmosphere, about 10 Israeli tanks and armoured personnel carriers rolled into Jenin late on Thursday in a sweep for militants after a three-hour operation in the West Bank city earlier in the day, witnesses said.

Hamas lobbed more than a dozen mortar bombs at Jewish settlements in the Gaza Strip and one of its makeshift Qassam rockets hit a house in Sderot, a town in southern Israel, but there were no reports of casualties.

- INDEPENDENT, REUTERS