Local legislators in Alabama's Jefferson County on Wednesday voted 4 to 1 to file for bankruptcy court protection in what would be the biggest U.S. municipal bankruptcy in history.

Despite a tentative deal with creditors reached in September to settle $3.14 billion of debt, county commissioners this week resurrected the threat of a Chapter 9 bankruptcy protection filing largely because the estimated savings from the September agreement had shrunk by about $140 million.

(This version corrects headline to 'city' from 'cty')

(Reporting by Melinda Dickinson)