The former US first lady tweeted a video of a group of dancers from Elijah Cummings' Baltimore district, hours after Trump launched an attack on the congressman.
“On #NationalDanceDay, I’m shouting out the Lethal Ladies, a Baltimore STEP team who I saw perform back in 2017. I’m so proud of you all – and everyone who’s dancing today!” Ms Obama wrote.
The video that Ms Obama shared shows a group of young women performing a routine to her slogan “when they go low, we go high”.
While Ms Obama, who was the world’s most admired woman in 2019 according to a YouGov poll, did not directly reference Mr Trump, her tweet was widely regarded as a rebuke to his recent remarks.
The US president attacked Mr Cummings in a series of vicious tweets on Saturday morning, which appeared to have been inspired by a Fox & Friends report that aired minutes before his outburst.
Mr Trump described the Baltimore district as a “filthy” and “rat and rodent infested mess” where “no human being would want to live”.
He later doubled down on his attack and shared a tweet from the far-right commentator Katie Hopkins, describing the city as a “s***hole”.
— Michelle Obama (@MichelleObama)July 27, 2019
The US president added that there was “nothing racist” about his tweets after he was widely criticised by a number of prominent Democrats including House Speaker Nancy Pelosi.
However, political commentators have noted that Mr Trump has used the word "infested" six times on his Twitter account – and each time it has been in reference to areas populated predominantly by people of colour.
Mr Trump’s attacks on Mr Cummings are just the latest in a weeks-long series of insulting tweets against minority members of Congress.
However, all four congresswomen are US citizens and only Ms Omar was born outside of the country.
Ms Obama appeared to weigh in on Mr Trump’s attack on the four lawmakers, tweeting that diversity is “what truly makes our country great".
“Whether we are born here or seek refuge here, there’s a place for us all," she added. “We must remember it’s not my America or your America. It’s our America.”
While Ms Obama did not directly reference the US president, her words appeared to echo Mr Trump’s campaign slogan “Make America great again”.