The violence in Gaza over the weekend was the worst since Hamas seized power a year ago after routing Fatah loyalists. Some 180 Palestinians fled into Israel after a Hamas crackdown on a clan linked to Fatah left 11 people dead and around 90 wounded (see page 29). Most were sent back. But their flight is likely to make the already fraught attempts to negotiate a peace settlement with the Palestinians more difficult.

The animosities that now divide the rival factions in Gaza and the West Bank make any Palestinian independent state comprising both entities unrealistic. The flight of so many Gazans into Israel, the enemy they have long opposed, recalls a similar flight after the Palestinians' defeat by the Jordanian Army during the Black September confrontation in 1970, and underlines the despair of those who fear revenge, torture and death at the hands of their rivals.

Some of those who fled Gaza are themselves Hamas supporters, but are also members of the powerful Helles clan that has opposed the Islamist Government in Gaza. They are likely to receive harsh treatment on their return. Israel considered sending the majority who backed Fatah to the West Bank. But this was opposed by Mahmoud Abbas, the Fatah-supported President, who feared that it would hand Hamas a victory by eliminating another opposition force in Gaza. His own Government has also come under pressure over the cost of housing hundreds of Fatah loyalists who fled from Gaza when Hamas seized control last year.

Despite the impending resignation of Ehud Olmert, the Prime Minister, Israel is still officially attempting to begin peace talks with Mr Abbas. It does not want to add to his difficulties. Those Gazans wounded in the assault on the clan's headquarters at the weekend will be allowed to remain in Israeli hospitals, but eventually they will probably also be returned to Gaza. This may be condemned by the outside world on humanitarian grounds, and will entrench the Hamas Government in power. But Israel has little option, especially if it does not want to give Hamas a pretext for breaking the ceasefire negotiated by the Egyptians six weeks ago.

The weekend events underline factors that make peace talks ever more distant. The first is the growing importance of clan politics in Gaza, where loyalties now have become tribal rather than ideological. Hamas is preoccupied with enforcing its own authority, and is unlikely to make any concessions on recognising Israel.

Secondly, public opinion in Israel is growing ever more hostile to peace talks with Palestinians who are so divided by internecine struggles. Mr Olmert has now almost no room for manoeuvre or initiative before his resignation next month, and may instead try to undercut any support for the Likud opposition at likely forthcoming elections by veering to the right. Settlement expansion will therefore continue apace.

Finally, the urgent task of ending the bloodshed in Gaza is likely to preoccupy international organisations as well as neighouring Arab Governments. As the approaching US election makes Washington's mediation less and less effective, there will be few ways of keeping anyone in the region focused on overall peace. And it is the absence of peace that makes bloodshed in Gaza all the more likely to reoccur.