Labor leaders said they were planning this move because they want to form an aggressively pro-growth coalition and because they believe the A.F.L.-C.I.O. is doing too little to organize nonunion workers.
This new coalition will be formed by the Service Employees International Union, the Teamsters, the laborers, the food and commercial workers and Unite Here, which represents hotel, restaurant and apparel workers, two union officials said. These officials insisted on anonymity because they feared some union leaders would be angry at them for disclosing the plan before it is announced Wednesday, after union leaders meet in Washington.
The five unions represent more than one-third of the membership of the A.F.L.-C.I.O., an umbrella federation of 57 unions and 13 million workers.
The union officials said the new coalition - tentatively called the Change to Win Coalition - would not compete with the federation. Rather, they say, it will complement the federation to give new energy and excitement to the flagging labor movement. Just one in 13 workers in the private sector is in a union, down from one in three a half-century ago.
But federation officials said yesterday that they feared that this new coalition would be competition and create an unnecessary distraction. One official questioned how effective the coalition would be in unionizing workers, considering that four of the five unions, except for the service employees, have been losing members.
The service employees' union, with more than 1.7 million members, is spearheading efforts to form this coalition at the same time that it is threatening to secede from the A.F.L.-C.I.O. At a meeting in San Francisco on Saturday, the service employees' executive board voted to give its top leadership authority to quit the main federation, if necessary.
"The union movement must focus on uniting with us the 9 out of 10 workers who have no union," the union's board said in a statement. "Without doing so, we not only cannot build a broad movement for social and economic justice, but we can't even win consistently at the bargaining table or in the legislative arena for the small minority of workers who still have a union."
Andrew L. Stern, the service employees' president, has said repeatedly in recent months that unless the main federation becomes far more aggressive about organizing nonunion workers, his union would pull out and seek to "build something stronger." Mr. Stern has also warned that his union would secede if Mr. Sweeney wins a new four-year term.
Mr. Sweeney, who has headed the labor federation for nearly a decade, said he had enough support to assure re-election at its convention in Chicago in late July.
Responding to the five unions' plan to create a new coalition, Mr. Sweeney said yesterday: "We all have the same goals, and we need to commit to work together to resolve the differences because if ever there was a time for the union movement to be united, this is it - with working people under the biggest assault in 80 years. Disunity just plays into the hands of the worst enemies of workers."
Mr. Stern has said that he hopes any new pro-growth union coalition will someday include the International Brotherhood of Carpenters, which quit the federation in 2001.
Union officials backing the new coalition say it will engage in multi-union organizing drives - something rarely done - seeking to unionize tens of thousands of workers at various major companies.
In recent weeks, several officials from the Teamsters, the food and commercial workers and Unite Here have hinted that their unions might also secede from the federation. But some of Mr. Sweeney's supporters say those threats are largely designed to increase pressure on him not to run for re-election.
