Unions representing nearly all of bankrupt Delphi Corp.'s US hourly workers reportedly said on Monday they have formed a coalition to fight proposed wage and benefit cuts they called an assault on working families.

The United Auto Workers, IUE-CWA, United Steelworkers, International Brotherhood of Electrical Workers, International Association of Machinists and the International Union of Operating Engineers said they formed the coalition on Thursday, according to a Reuters report.

"We are outraged by Delphi's attempt to use the bankruptcy process to dictate the radical destruction of the living standards of America's industrial workers ...," the coalition said in a statement cited by the news agency.

Unions leaders told Reuters the cost-cutting demands are especially hard to swallow when Delphi also plans cash and equity bonuses for several hundred executives as incentives to stay with the company through its reorganisation.

According to the report, the unions represent about 33,650 Delphi workers - the company has about 50,000 US workers, including 34,750 hourly employees.