Defense Minister Ehud Barak's opponents in the Labor Party warned him Monday that he must begin fighting Finance Minister Ronnie Bar-On's proposal for the 2008 state budget or they will begin fighting him. Barak has enjoyed a grace period since his June 12 election as Labor Party leader, with no MK in his faction criticizing him publicly. But behind the scenes, the MKs who did not support him in the Labor leadership race have grown increasingly angry at him. Unlike the reception for previous budgets, since Bar-On unveiled his proposal on Sunday morning, no coalition partners have threatened to quit and no minister has issued an ultimatum about resigning if changes are not made. The first cracks in the quiet came Monday from Labor's backbenches. "We can't vote for such a budget and we will have to fight against it," said MK Yoram Marciano, who Barak fired as Labor whip last week. "The rise in the minimum wage is delayed. There is nothing about rehabilitating poor neighborhoods. Everything we fought for in the past is gone." Marciano mocked Barak for seeking additional funds for the Defense Ministry while not doing enough to help the poorest sectors of the population that Labor championed when it was led by Barak's predecessor, MK Amir Peretz. "It's important to be ready for the next war, but you can also die from hunger, not just from war," Marciano said. "If he doesn't fight the budget, many MKs will fight against him. There will be action in the party again." Peretz broke his silence since the Labor race on Monday, telling a reporter from the Ynet Web site while on vacation in the United States that he would fight against Barak's "anti-socioeconomic" policies upon his return to Israel. MK Ami Ayalon, who ran against Barak, has been careful not to criticize him since the race and is expected to be appointed a minister soon. His ally, MK Avishay Braverman, is expected to fight against Barak's handling of the budget and other socioeconomic issues. He is a member of a committee headed by Agriculture Minister Shalom Simhon that Barak formed to decide Labor's approach to the budget.