1 of 7 | The logo of U.S. Steel logo is seen at the Edgar Thomas Plant, a steel mill near Braddock, Pa., before President Donald Trump's arrival on Friday. Photo by Archie Carpenter/UPI | License Photo

May 30 (UPI) -- President Donald on Friday announced a 50% tariff on steel made outside the United States as he touted a partnership between Japan's Nippon Steel Corporation and the United States Steel Corporation during a rally near Pittsburgh.

Calling it the "heart of U.S. Steel," Trump spoke at the company's headquarters in Allegany County. The indoor rally began around 5:30 p.m. and ended one hour later.

Steelworkers wearing hard hats sat behind him, with some called to the podium to praise the deal and Trump.

During the appearance, he announced the tariff change.