Washington (CNN) Senate Minority Leader Chuck Schumer invoked first lady Melania Trump's "Be Best" initiative in a response to President Donald Trump's tweet Thursday morning calling him "Cryin' Chuck."

"Senator Cryin' Chuck Schumer fought hard against the Bad Iran Deal, even going at it with President Obama, & then Voted AGAINST it!" Trump wrote on Twitter Thursday morning. "Now he says I should not have terminated the deal - but he doesn't really believe that!"

"#BeBest" the New York Democrat responded, referencing Melania Trump's newly announced initiative, which encourages children to use the internet in positive ways.

The program, which Mrs. Trump unveiled on Monday includes efforts to tamper down cyberbullying and negativity, despite her husband often using Twitter for name-calling and attacks.

During the campaign and his presidency, Trump has used nicknames for his critics and opponents, such as "Lyin' Ted" Cruz, "Little Marco" Rubio or "Sloppy Steve" Bannon.

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