That cease-fire was supposed to allow a breathing space to try to get the political process back on track.

Israel's helicopter attack left four people dead

Instead there has been a gradual descent into further violence.

Both sides are blaming each other for the collapse of the cease-fire.

Palestinians condemn continuing incursions by Israeli troops into areas under Palestinian control. They point to the targeted killing of Palestinian activists - indeed it was the helicopter attack on the head of the Hamas military organisation in Bethlehem that left four people dead that provoked the mortar attack on Gilo.

The Israelis for their part insist that the Palestinian Authority has not done enough to curb the activities of groups like Hamas. Bomb attacks have continued.

On Tuesday night Israel massed troops and armoured units south of Bethlehem and north of Jenin.

It is still not clear if this is a demonstration or whether Israel intends to make a significant incursion into Palestinian areas.

Huge cost

Such scenarios have been the subject of war games in the past and Israel's military commanders know that such a move could be extremely costly in terms of civilian lives, not to mention Israel's standing abroad.

Most military experts agree that it would serve as little more than a warning.

Analysts believe there is no definitive military answer to the intifada.

But pressure for action among sections of the Israeli public is growing.

The danger is that any large-scale military move could effectively lead to an overt war between Israel and the Palestinian Authority. This would solve little but would end any chance of meaningful political progress for the foreseeable future.