PITTSBURGH (AP) — Vice President Joe Biden is marking the Labor Day holiday with a stop in Pittsburgh.

The vice president is donning a black-and-gold United Steelworkers union hat and telling hundreds of union members that the gap between the wealthy and poor is hurting the nation.

Biden says the nation's tax code is "simply not fair" and the "wealthy aren't paying their fair share." The vice president is joining AFL-CIO President Richard Trumka at the city's annual Labor Day parade.

Biden is seriously considering a late entry into the 2016 Democratic presidential campaign.

He said last week he wasn't certain if he and his family had the "emotional energy" for another campaign.

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