PITTSBURGH (AP) - U.S. Steel says it is laying off 677 workers in the United States and Canada because of weakening customer demand.

United States Steel Corp. spokesman John Armstrong says the layoffs are effective immediately for 500 employees in the United States and 177 in Canada.

The layoffs affect workers at Pittsburgh-based U.S. Steel's facilities in the Pittsburgh area; northwest Indiana; Fairfield, Ala.; Ecorse and River Rouge, Mich., and Granite City, Ill.

In Canada, U.S. Steel is laying off workers at its Hamilton and Erie plants.

Armstrong says the jobs will come back "when we see customer demand strengthening."