President Trump joked that he didn't know about teenage climate activist Greta Thunberg before she was named Time magazine’s ‘Person of the Year.’

“This year, I lost to Greta,” Trump told the enthusiastic crowd at the Conservative Political Action Conference in National Harbor, Maryland, on Saturday. “I said, ‘Who?”

President @realDonaldTrump talks about Time's Person of the Year.



"This year I lost to Greta... I said 'who?'" pic.twitter.com/pR1pdHKtdg — Daily Caller (@DailyCaller) February 29, 2020

“I’m not going to get involved in that because, last time, I got in a little trouble,” the president added, prompting a laugh from the crowd.

Trump has been criticized for tweeting and commenting about the 17-year-old Thunberg, who rose to prominence following a speech she gave at the United Nations warning about the devastation of climate change.

“She seems like a very happy young girl looking forward to a bright and wonderful future. So nice to see!” the president sarcastically tweeted about Thunberg in September. In response to Trump's digs, Thunberg is known to change her Twitter bio to reflect the criticism.

She seems like a very happy young girl looking forward to a bright and wonderful future. So nice to see! https://t.co/1tQG6QcVKO — Donald J. Trump (@realDonaldTrump) September 24, 2019

During his speech Saturday, Trump said it “doesn’t matter” he lost the award to Thunberg because he’s “won it enough.”

Trump’s speech at CPAC was the third time he’s made an appearance since being elected president. He promised the crowd he would be attending again next year.

“Look forward to being with all of my friends and supporters @CPAC on Saturday, February 29th! #KAG2020,” Trump tweeted earlier this week.