Donald Trump's Odd Reaction To Greta Thunberg's Scathing UN Speech

The US President has met Greta Thunberg's condemnation of climate inaction with sarcasm, calling her scathing speech "nice to see".

The teenage climate activist took world leaders to task on Monday, accusing nations of robbing her of a future through climate inaction, during an impassioned opening speech at the United Nations Climate Action Summit.

“This is all wrong. I shouldn’t be up here. I should be back in school on the other side of the ocean, yet you all come to us young people for hope. How dare you,” said the Swedish teenager, her voice quivering.

“You have stolen my dreams and my childhood with your empty words."

Visibly angry and emotional, Thunberg's words quickly made waves across the world.

Tweeting a video of the speech on Tuesday, Donald Trump commented the 16-year-old seems to be "very happy", in what appears to be a sarcastic response to the address.

"She seems like a very happy young girl looking forward to a bright and wonderful future," Trump said.

"So nice to see!"

READ MORE: Greta Thunberg Filmed Giving Donald Trump A Death Stare

The interactions between Thunberg and Trump during the summit have been under scrutiny, given the president's history as a climate change denier.

As Trump made his way to a UN meeting about religious freedom after attending the major climate summit for a few minutes, cameras captured the moment Thunberg locked eyes on the passing leader.

Many were quick to hone in on the teenager's icy cold glare, and the brief encounter went viral.

Before she set sail on a solar-powered boat headed to the UN summit, Thunberg was asked if she would be open to a meeting with Trump. The activist said such a meeting would be a "waste".

"Why should I waste time talking to him when he, of course, is not going to listen to me?" she said.

READ MORE: 'You Stole My Childhood': Emotional Greta Thunberg Puts World Leaders On Blast

Thunberg is one of 16 young climate activists who filed a landmark complaint with the United Nations on the Rights of the Child, accused five countries of violation children's rights by failing to adequately combat the climate crisis.

The complaint accuses Germany, France, Argentina, Brazil and Turkey -- some of the biggest polluting nations to sign the 1989 Convention of the Rights of the Child -- of doing nothing to address the impact of rising carbon emissions despite knowing the impact.

READ MORE: Climate Activist Greta Thunberg Says Meeting Trump Would Be A 'Waste'

It was Thunberg's solitary weekly protest outside the Swedish parliament a year ago which inspired millions of young people to take to streets in more than 150 countries on Friday, demanding governments commit to serious climate action.