U.S. President Donald Trump, the most powerful person in the world, took to Twitter Thursday morning to vent his frustration on a pressing matter: TIME magazine's selection of 16-year-old Swedish climate activist Greta Thunberg as 2019's Person of the Year.

Trump, who was reportedly a finalist for the award, attacked Thunberg in a tweet meant to ridicule the teen's righteous rage over the climate crisis and political inaction to address it on the part of global leaders.

"So ridiculous," tweeted Trump. "Greta must work on her Anger Management problem, then go to a good old fashioned movie with a friend! Chill Greta, Chill!"

As Common Dreams reported Wednesday, Thunberg was named Person of the Year for her role in beginning the global youth climate strike movement. Thunberg responded to receiving the award by tweeting that the honor was "unbelievable" and citing the movement as a whole.

Wow, this is unbelievable! I share this great honour with everyone in the #FridaysForFuture movement and climate activists everywhere. #climatestrike https://t.co/2t2JyA6AnM pic.twitter.com/u4JUD4cgCz — Greta Thunberg (@GretaThunberg) December 11, 2019

Thursday was just the latest instance of Trump complaining over not being selected as the magazine's Person of the Year—the president, who received the honor in 2016, whined about the selection process in 2015 and claimed in 2017 that he rejected the award.

According to The Washington Post:

In 2015, as a candidate for president, Trump took to Twitter to complain after Time chose German Chancellor Angela Merkel for her leadership in the Greek debt crisis and European migrant crisis. ... In 2017, Trump weighed in again on the selection process, writing on Twitter: "Time Magazine called to say that I was PROBABLY going to be named 'Man (Person) of the Year,' like last year, but I would have to agree to an interview and a major photo shoot. I said probably is no good and took a pass. Thanks anyway!"

The president's remarks on Thunberg Thursday sparked anger and disgust from observers, including tweeting liberal doctor Eugene Gu.

"Greta Thunberg is dedicating her life fighting climate change because her generation has to deal with the rising seas, wildfires, hurricanes, food shortages, and hell on Earth because of all the rich old people like Trump sucking this planet dry for oil like vampires," said Gu. "Be best."

While Thunberg did not respond directly to the president, she did update her bio on Thursday to read: "A teenager working on her anger management problem. Currently chilling and watching a good old fashioned movie with a friend."