Story highlights Former Labor Secretary Robert Reich calls out Donald Trump's tweet: 'Stop this'

"This is bullying. This is not using the bully pulpit," Robert Reich said.

(CNN) Former Labor Secretary Robert Reich called out President-elect Donald Trump on Wednesday for lashing out at a union leader who criticized the Carrier jobs deal.

"With all due respect, Mr. Trump, you are our President-elect of the United States," Reich said on "Anderson Cooper 360." "You are looking and acting as if you are mean and petty, thin-skinned and vindictive. Stop this. This is not a fireside chat."

Moments after the president of the United Steelworkers Local 1999, Chuck Jones, appeared on "Erin Burnett OutFront" and was critical of Trump's claim that he saved 1,100 jobs at the Indianapolis factory, Trump slammed the union boss on Twitter.

"Chuck Jones, who is president of United Steelworkers 1999, has done a terrible job representing workers. No wonder companies flee country!" Trump wrote.

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