(Reuters) - Detroit Mayor Dave Bing said on Friday that 1,000 city worker positions, or about 9 percent of the total, would be cut, two days after he said the city would run out of cash by April without broad wage and benefit cuts and a corporate tax increase.

City departments will identify the number of workers to be laid off starting the first week of December and layoff notices will be issued starting the week of January 21, the mayor's office said in a statement.

The jobs are to be eliminated by February 25 to save Detroit about $14 million in the current fiscal year, Bing said. Earlier on Friday, the mayor's office had said that layoff notices would begin the first week of December.

Bing had warned on Wednesday that Detroit faced a $45 million cash shortfall by the end of the fiscal year in June 2012 without reductions that would include pay cuts for police and fire department workers.

Bing said on Wednesday the cuts were needed to avoid the city falling under a state-appointed emergency manager, which would take control over Detroit from local residents.

Several Michigan cities, including Pontiac and Benton Harbor, as well as the Detroit Public Schools, have been put under emergency manager control. Under Michigan law, emergency managers have broad powers to rewrite agreements with union workers and take control from local governments.

The mayor said Friday he was also initiating an immediate hiring freeze, with the exception of the Detroit water and sewer department that is under federal court order.

(Reporting by David Bailey; Editing by Jerry Norton)

(The story adds the city's correction of the timing of layoffs in second paragraph)