Washington (CNN) President Donald Trump mocked Swedish climate activist Greta Thunberg on Twitter late Monday night after the 16-year-old excoriated world leaders for not doing enough to tackle the climate crisis.

"She seems like a very happy young girl looking forward to a bright and wonderful future. So nice to see!" Trump posted on Twitter, replying to a video of Thunberg's speech at the United Nations climate action summit earlier in the day.

Trump's penchant for Twitter insults and online confrontations with people he sees as political adversaries is well known, though Monday's tweet is a striking display of the President teasing a child.

Thunberg appeared to take Trump's slight in stride. By late Tuesday morning, she had updated her Twitter bio to read: "A very happy young girl looking forward to a bright and wonderful future."

In the video shared by Trump of her speech, Thunberg is visibly frustrated and at times appears to be holding back tears of anger as she dresses down the UN General Assembly.

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