According to sources, outgoing Labor Party Chairman and Defense Minister Amir Peretz said newly-elected labor chairman Ehud Barak had "ruined his chance to prove his willingness to cooperate" with the outgoing Labor leader.

"The old Barak is back," Peretz said in private conversations on Saturday, according to his confidantes.

Peretz was referring to the speed with which newly-elected Labor Party Chairman Ehud Barak secured his own appointment as Defense Minister.

In light of Hamas' violent takeover of the Gaza Strip, Barak sent a letter to Prime Minister Ehud Olmert asking he be made defense minister instead of Peretz as soon as possible.

Barak and Olmert met Friday and "agreed that given the situation in the Palestinian Authority, we need an experienced defense minister as soon as possible," an Olmert aide said on condition of anonymity.

Defense Minister Amir Peretz resigned from the government on Friday, Channel 10 reported, as the cabinet approved the appointment of Barak as his replacement.

The Knesset is expected to approve Barak's appointment on Monday, immediately following which he will take over from Peretz.

Peretz said in the wake of the Winograd Committee's partial report on the Second Lebanon War that he would resign as defense minister following the Labor Party primaries.

There had been speculation that he would stay on in the government as a minister without portfolio, but he informed Ehud Olmert on Friday that he does not intend to do so, Channel 10 reported.

Deputy Defense Minister Ephraim Sneh will also likely be replaced.

Barak made it clear to Olmert that he intends to stick to his demand that the prime minister resign no later than the publication of the Winograd Committee's full report - in late July or early August.

Olmert will meet Barak again at the end of next week, after his return from the United States. Upon returning, the prime minister also plans to appoint a finance minister and a Negev and Galilee development minister, to replace President-elect Shimon Peres. Both these portfolios are expected to remain in Kadima's hands.

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