Erin Jensen | USA TODAY

AP, AP

Meeting with President Donald Trump is not on Greta Thunberg's to-do list.

The 16-year-old environmental activist shared on Friday's episode of "The Ellen DeGeneres Show" that she doesn't have interest in meeting with the nation's leader.

"Do you ever think about – would you sit down with him to try to help him understand climate change?" the host asked.

"I don’t understand why I would do that," Thunberg said to laughter and applause from the audience. "I don’t see what I could tell him that he hasn’t already heard, and I just think it would be a waste of time, really."

Donald Trump mocks teen climate activist Greta Thunberg in late night tweet

Thunberg said she learned of climate change age at an early age in school.

"I learned the basics, like the planet was warming because of increased greenhouse gasses," she recalled, "and then I just couldn't believe it because I thought if this was really true, then surely, someone must've done something. Then, surely, we would take it seriously. But no one took it seriously."

In September, Trump sarcastically praised the teen on Twitter, sharing a clip of her impassioned speech at the UN.

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Thunberg scolded hundreds of world leaders at the UN saying through tears: "How dare you! You have stolen my dreams and my childhood with your empty words, and yet, I am one of the lucky ones.”

She continued: “How dare you continue to look away and come here saying that you are doing enough when the politics and solutions needed are still nowhere in sight."

"She seems like a very happy young girl looking forward to a bright and wonderful future," read Trump's Sept. 23 post on social media. "So nice to see!"

Following criticism of her speech, celebrities like Anne Hathaway, Priyanka Chopra and Chrissy Teigen offered support for the young activist.

Thunberg also earned the praise of Leonardo DiCaprio, who revealed on Instagram Friday he met the teenager. Captioning a post of the two sitting and smiling side-by-side, the "Once Upon a Time in Hollywood" star hailed Thunberg as "a leader of our time."

"There are few times in human history where voices are amplified at such pivotal moments and in such transformational ways," he wrote. "History will judge us for what we do today to help guarantee that future generations can enjoy the same livable planet that we have so clearly taken for granted."

He continued: "I hope that Greta’s message is a wake-up call to world leaders everywhere that the time for inaction is over. It is because of Greta, and young activists everywhere that I am optimistic about what the future holds. It was an honor to spend time with Greta. She and I have made a commitment to support one another, in hopes of securing a brighter future for our planet."

Contributing: John Fritze, Charles Trepany

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