Matt Lauer and his former colleagues at NBC's Today show have addressed the rape allegations made against Lauer by a former NBC employee as part of Ronan Farrow's new book, Catch and Kill.

In an open letter released Wednesday to multiple outlets, Lauer wrote that he considered his "silence" on the claims made by former NBC News employee Brooke Nevils a "mistake."

"In a new book, it is alleged that an extramarital, but consensual, sexual encounter I have previously admitted having, was in fact an assault," Lauer wrote. "It is categorically false, ignores the facts, and defies common sense." (Representatives for Lauer did not respond to TV Guide's request for comment.)

Overnight on Tuesday, Variety reported that Catch and Kill features an interview between Farrow and Nevils, who alleged that Lauer anally raped her at the 2014 Olympics in Sochi. Her complaint against Lauer led to his firing from NBC in 2017. Nevils' identity was kept anonymous at the time at her request; this is the first time the details of her allegations are being made public.

"It was nonconsensual in the sense that I was too drunk to consent," Nevils told Farrow, per Variety. "It was nonconsensual in that I said, multiple times, that I didn't want to have anal sex."

Farrow's book also says that after Lauer's firing, Nevils learned that Noah Oppenheim, president of NBC News, and Andrew Lack, chairman of NBC News and MSNBC, "were emphasizing that the incident hadn't been 'criminal' or an 'assault.'" Nevils eventually took medical leave and a seven-figure payment.

In a memo to NBC News staff obtained by TV Guide late Wednesday, Lack called Lauer's conduct "appalling and reprehensible" and defended the organization's use of the term "sexual misconduct" to describe the former anchor's alleged assault. "Today, some have questioned why we used the term 'sexual misconduct' to describe the reason for Lauer's firing in the days following. We chose those words carefully to precisely mirror the public words at that time of the attorney representing our former NBC colleague," Lack wrote.

Of the NBC News culture since Lauer's ouster, he added, "In the past two years we have taken significant steps to improve our culture and ensure we have a workplace where everyone feels safe and respected, as well as protected in raising claims. Since then, we've required all NBC News employees to complete in-person workplace behavior trainings and we've significantly increased awareness of the ways employees can report concerns - anonymously or otherwise."

NBC News' Morgan Radford addressed Variety's report on Today on Wednesday morning, followed by a response from anchors Savannah Guthrie and Hoda Kotb.

"I feel like we owe it to our viewers to pause for a moment," Guthrie said. "This is shocking and appalling, and I honestly don't even know what to say about it. I want to say that I know it wasn't easy for our colleague Brooke to come forward then, it's not easy now, and we support her and any women who have come forward with claims. And it's just very painful for all of us at NBC and who are at the Today show, and, you know, it's very, very, very difficult."

Kotb then recalled their first broadcast following the news of Lauer's firing in 2017. "We don't know all the facts in all of this, but they're not allegations of an affair, they're allegations of a crime, and I think that's shocking to all of us here who have sat with Matt for many, many years," Kotb said. "I think we're going to continue to process this part of this horrific story. And as you said, our thoughts are with Brooke. It's not easy what she did to come forward. It's not easy at all."

In a statement shared on Today, NBC News emphasized that it had responded swiftly to Nevils' complaint: "Matt Lauer's conduct was appalling, horrific, and reprehensible, as we said at the time. That's why he was fired within 24 hours of us first learning of the complaint. Our hearts break again for our colleague."

See Today's full report and Guthrie and Kotb's responses below.

This post has been updated throughout.