Lauer’s co-host Savannah Guthrie made the announcement during the opening of the show Wednesday.
“This is a sad morning here at Today and NBC News,” Guthrie said before reading a statement sent to staff by NBC News chairman Andrew Lack.
In the statement, Lack said an employee came forward Monday night to report Lauer for inappropriate sexual behaviour in the workplace.
WATCH BELOW: Katie Couric says Matt Lauer ‘pinches her a** a lot’ in 2012 interview
“It represented, after serious review, a clear violation of our company’s standards. As a result, we’ve decided to terminate his employment,” Lack said in the statement.
“While it is the first complaint about his behavior in the over twenty years he’s been at NBC News, we were also presented with reason to believe this may not have been an isolated incident.”
After reading the statement, Guthrie said, “As I’m sure you can imagine, we are devastated and we are still processing all of this. All we can say is we are heartbroken; I’m heartbroken.”
Guthrie described Lauer as “a dear, dear friend,” and said she was “heartbroken for the brave colleague who came forward to tell her story.”
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She then asked rhetorically, “How do you reconcile your love for someone with the revelation that they have behaved badly?”
The move comes a week after CBS News fired morning anchor Charlie Rose amid reports of sexual misconduct.
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U.S. President Donald Trump was quick to respond to the firing, posting tweets almost immediately after the news broke.
Lauer, 59, has been a fan favourite on Today for more than two decades. He first joined the show in 1994 as a news reader; within four years he was the show’s co-anchor. He’s worked alongside noted and respected journalists Meredith Vieira, Katie Couric and Ann Curry over the course of his tenure.
In a 2012 interview on Watch What Happens: Live, Couric told host Andy Cohen that Lauer “pinches me on my a** a lot.” (You can watch this exchange in the video mid-article, above.) Cohen had asked her what Lauer’s most annoying habit was.
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NBC negotiated a deal with Lauer in 2016 to keep him on the air through 2018, but obviously that deal is now moot.
Lauer’s wife, Annette, filed for divorce in 2006, accusing him of “cruel and inhumane behaviour,” but withdrew the filing shortly afterwards when they reached a private agreement.