Which way now for Israel after Ariel Sharon?

Benjamin Netanyahu

The charismatic but quixotic politician who became Ariel Sharon's bitterest rival is easily the most right-wing of the main candidates. He may try to trim to the centre during the campaign to suck votes back but will be severely constrained in how far he can do so before or after the election.

This makes him by a long way the least likely of the main players to prepare concessions, such as withdrawal from tracts of the West Bank, negotiated or unilateral. If he does so - perhaps under US pressure - he is likely to fall foul of right-wing groups such as the settlers' organisation, the Yesha Council, which supported him for the Likud leadership on the strength of his opposition to Gaza disengagement. His opportunistic resignation over the Gaza withdrawal did much to push Mr Sharon into abandoning Likud and forming his own party. Mr Netanyahu irritated Bill Clinton during his tenure as Prime Minister from 1996-99 for, in effect, abandoning the Oslo accords. If there is a Hamas victory in this month's Palestinian poll or an outbreak of serious Palestinian violence in the run-up to Israeli polling day in March, he will be under international pressure to make concessions.

Shimon Peres

The octogenarian former prime minister is more likely to be an éminence grise of Mr Sharon's new party, Kadima, than its leader. Fresh attempts may even be made to lure him back to the Labour Party. Although one poll has put him top of the list of preferred prime ministers after Mr Sharon, he has a record of failure in elections and most Kadima members are former Likudniks, who would prefer one of their own in the top job. As a Nobel Prize-winning architect of the Oslo accords, Mr Peres is likely to be keener than some of his more unilateralist Kadima colleagues on negotiations with the Palestinians. But whether he would go further than they would in making enough concessions to secure a lasting agreement is much more doubtful. Mr Peres has been accused of doing whatever it takes to stay in office. The best hope that he might be prepared to push for the leadership could be a desire to go down in history as a peacemaker - a role snatched from him by the collapse of Oslo.

Amir Peretz

Of all the potential candidates, the Morocco-born former union leader who spectacularly wrested the Labour leadership from Shimon Peres last November has the most deeply felt and long-standing commitment to a two-state solution. He has long articulated his belief that the costs for Israel in continuing to occupy the West Bank hurt Israel as well as the Palestinians. He was careful at the outset of his leadership to state his commitment to negotiations with the Palestinian leadership. By that he means talks on a "final-status" settlement. Like Mr Sharon, he would probably envisage keeping the main semi-urban settlement blocks under Israeli control; but some Labour officials are promoting a Hong Kong-style formula in which the settlements would be "leased" from the Palestinians in return for financial or territorial compensation.

Ehud Olmert

If the acting Prime Minister assumes the position permanently, he will promote the Sharon agenda. The big difference is that he will be under greater pressure than was Mr Sharon to clarify what that agenda is. Mr Olmert has been more explicit in saying that Israel cannot expect indefinitely to control the lives of Palestinians and in insisting that withdrawal from Gaza was not merely a means of hanging on to the West Bank. With Mr Olmert at its helm, the Kadima party will be pressed to say if it plans unilateral withdrawals from the West Bank should Mr Abbas fail to disable armed factions.

Mr Olmert was first elected to parliament at the age of 28, and served seven terms. He was investigated several times for corruption, but was never convicted. Elected Mayor of Jerusalem in 1993, he held the post for 10 years, supporting Israeli moves to settle in Palestinian-dominated areas of the city.