Katie Couric says she has no relationship with Matt Lauer

Katie Couric says she has "no relationship" with Matt Lauer, her former US Today show co-anchor who was fired in 2017 for inappropriate sexual behaviour.

She spoke out on her former show on Tuesday to promote the release of her new memoir, Going There. In an interview with current Today host Savannah Guthrie, Couric said the scandal took her a "long time to process" because she didn't know that side of Lauer.

"As I got more information and learned what was going on behind the scenes, it was really upsetting and disturbing," she said, adding that it was "really devastating, but also disgusting."

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Couric admitted in the Today interview that there was a side of Lauer that she "never really knew," and she tried to understand why he was so "abusive to other women."

The book also contains text messages between Couric and Lauer that showed how their relationship "devolved and ultimately deteriorated."

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"We have no relationship," Couric stated. She and Lauer anchored the NBC morning show together for nearly a decade before she left in 2006 to host CBS Evening News.

In 2017, Lauer said he was "truly sorry" for the pain he has caused. Last year, he denied a rape allegation brought to light by author Ronan Farrow. Lauer could not immediately be reached for comment.

Couric's book is being released on October 26.