President Mahmoud Abbas has no intention of going down in history as the man who legitimised the permanent and possibly fatal division of the Palestinian independence movement.

But he has called an election for January that could be a nail in the coffin of Palestinian unity, assuming his Islamist political rivals in control of the Gaza Strip are serious about their threat to ban the vote on their territory.

The outcome of an election held in the West Bank but not in the Gaza Strip would be "worse than the two Koreas", said Zakaria al-Qaq, an expert on national security issues.

"Here we would see a total rupture for a long period of time," Qaq said. Gaza would be cut off and the West Bank would end up as little Gazas, with "transportational continuity rather than territorial continuity".

So why would Abbas take such a gamble?

Political analysts say he knows Israel feels no pressure to negotiate a peace treaty ending its occupation of the West Bank as long as Abbas's Fatah and Hamas -- which refuses to recognise Israel's right to exist -- are divided.

With U.S.-brokered peace negotiations stalled and diplomatic wheels spinning, the Western-backed leader's credibility with his people is bleeding away. He needs to change tack, pick a winning strategy and re-set the starting line for talks.

Last Friday, ahead of a new round of U.S. shuttle diplomacy beginning this weekend, he issued a decree setting Jan. 24 as the date for parliamentary and presidential elections in all the Palestinian territories.

Hamas immediately and predictably rejected the call.

Analysts said Abbas has made Palestinian unity his priority goal and chosen the election deadline as his strategy. He is using it to persuade Hamas to make peace with the Fatah movement and end the deep split in Palestinian ranks.

"Abbas is aware that as long as he negotiates with Israel while he's not in control of Gaza, the Israelis won't give him anything," said Bassem Zubeidi, political analyst at Birzeit university in the West Bank. After all, he points out, "they didn't concede anything when the Palestinians were united."

"The only game in town is to end the split. Abbas is taking this path and elections are his strategy," Zubeidi said.

ROLL OF THE DICE

U.S. President Barack Obama's peace envoy George Mitchell arrived back in the region on Thursday to resume shuttle diplomacy aimed at breaking this deadlock, and Secretary of State Hillary Clinton was due in Israel on Saturday night.

Abbas, 74, has a lot riding on the outcome.

Officials say he told Obama last Friday he would not run for re-election unless Israel agreed to freeze the building of settlements in the West Bank, thereby allowing him to resume peace talks without losing all credibility.

Hamas, which advocates the continuation of what it calls armed struggle against "the Zionist occupiers", would bury Abbas in Gaza if he buckled on this demand. He has already been denounced there as a "traitor" in small demonstrations approved by the Islamists.

But while the rival factions remain hostile and now appear to be on a collision course, both have left the door open for compromise.

A senior Palestinian official said Abbas would immediately postpone elections if Hamas agreed to a reconciliation pact mediated by Egypt and accepted by Fatah, even if it came at the very last minute, "on January 23rd".

Holding the ballot in January without Hamas would mean cutting Gaza loose from the West Bank, a massive blow to Palestinian statehood aspirations, analysts believe.

It seems unlikely that the brinkmanship can be dragged out for very long. The Central Election Commission said on Thursday that election nominations would open on November 30 and close 12 days later, putting the electoral process firmly on track.

If Hamas still reject a deal, Abbas can condemn them for putting their factional interests above those of 4 million Palestinians, but he will have to live with the ramifications.

"Elections would deepen divisions to a great extent in a way that will hurt Abbas and Hamas equally. This would be suicidal. Personally I cannot see the political gains," Zubeidi said.

Hamas stunned Fatah and its Western backers in 2006 by winning parliamentary elections, forcing Abbas into a political cohabitation with a movement opposed to peace with Israel as a means to ending occupation, which is his main goal.

This lasted half a year before Abbas dissolved the government. In violent clashes in 2007 Hamas drove Fatah out of Gaza.