UN and America say multinational force is only way to end violence

As violence threatens to engulf the barely launched roadmap plan for peace in the Middle East, calls are growing for a large-scale international force to be sent in, as the only hope of imposing some sort of a ceasefire between Israelis and Palestinians.

The demands came as a team of US monitors arrived in the region, and - after intense pressure from Washington and Arab countries - Palestinian and Israeli security officials agreed to resume contacts. This follows a week of bloodshed during which at least 50 people died.

The dispatch of a multinational force is increasingly seen as the only means of securing a breathing space, allowing meaningful negotiations to begin.

In an interview with an Israeli newspaper, the United Nations Secretary General, Kofi Annan, described the US monitors as "a beginning". But, he said, only a substantial armed force could halt the fighting. More significant are similar calls from Capitol Hill, long a staunch ally of the Israeli cause.

Senator John Warner, the Virginia Republican who heads the powerful Senate armed services committee, says that a robust Nato force should be dispatched, since it was clear that both Israelis and Palestinians had "lost control of events". Martin Indyk, a former US ambassador to Israel, believes the West Bank and Gaza should be made a trusteeship, so that a Palestinian government could take shape as international forces maintained security.

Such an idea has long been backed by Palestinians. But Israel, deeply suspicious of entrusting its security to foreigners other than Americans, has always rejected it. For his part, Mr Bush is unwilling to put US troops at risk in so volatile an environment, although he may have little choice if the violence is to be halted and the roadmap plan resumed.

The President's hands are also tied by US domestic support for Israel. In a rare rebuke to the Prime Minister, Ariel Sharon, he professed himself "deeply troubled" by Israel's attempt to assassinate a leading Hamas politician. But after Hamas retaliated with the Jerusalem suicide bombing that killed 16 people on Wednesday, the White House was again placing the entire blame on the militant group.

That, however, only weakens the US-sponsored Palestinian Prime Minister, Mahmoud Abbas, by highlighting his inability to stop terrorist attacks. "The basic problem is the lack of a Palestinian capacity to deal with the terrorists," Mr Indyk says.