Prime Minister Ariel Sharon and Labor Party chairman Shimon Peres have agreed in principle that if a national unity government is formed, it will last until November 2006 - when elections are scheduled to be held, say senior Likud and Labor sources.

The commitment of the two sides will appear in an outline of the coalition agreement the two parties will sign, the sources said. At this point, Labor's entry into a coalition government is conditional on a decision backing this move in the Likud Central Committee, which is to vote next week.

Peres told Haaretz that he rejected the proposal of several members of Labor that the party would withdraw from the coalition government immediately after the completion of the disengagement from Gaza and northern West Bank. Such a withdrawal would bring about the collapse of the government and early elections.

"I am interested in staying in the government also after the disengagement plan is carried out," Peres said, "so that I can be a partner in future moves. This will not end with the disengagement. The disengagement must lead to the implementation of the road map, and we must be there in order to emphasize that this is our position."

The veteran statesman added: "In all modesty, I can say that my international standing and my relations with the Palestinians can be significant at this time and in this situation."

Sources close to the prime minister confirmed that Sharon would like to avoid early elections and this will be one of the demands he poses to Labor during negotiations for a coalition.

Still, in Labor there was general pessimism about the chances that the Likud will alter its stance and allow Sharon to invite Labor to join the government.

Sharon and Peres share an interest in maintaining a partnership as long as possible because it is likely to restrain internal challengers. Sharon is faced with the competition of Finance Minister Benjamin Netanyahu, and Peres is challenged by former prime minister Ehud Barak and others in his party.

Primaries to be postponed

Labor pundits said last night that if indeed a coalition government is created, moves to expedite the primaries for the party leadership will be postponed to the start of 2006. All potential candidates, with the exception of Ehud Barak, are likely to be members of the coalition cabinet, and Barak may find himself completely outside the arena where he can have political influence.

Peres made it clear earlier this week that contrary to some reports, he was not involved in the efforts to bring about a postponment of Labor primaries when the party central committee gathered on Tuesday. Peres insisted that during the meeting in his office prior to the vote, he did not take a stand when the proposal was put forward to postpone the primaries.