Ellen DeGeneres has said she “didn’t understand” the allegations of a toxic work environment made about her talk show and that guests only spoke of the programme’s “happy atmosphere”.

The comedian and TV presenter, who announced on Wednesday that the programme is ending after 19 years, has addressed the controversy in a broadcast interview for NBC’s Today show in the US.

Last summer, DeGeneres, one of the most high-profile figures on TV in America, came under intense scrutiny after media reports detailed claims made about an allegedly toxic workplace, and three top producers left.

In a preview clip for her Today interview, the 63-year-old star is asked whether she felt like she was being “cancelled”.

She replied: “I really didn’t understand it. I still don’t understand it. I thought something was going on that… because it was too orchestrated. It was too coordinated.

“And people get picked on, but for four months straight for me, and then for me to read in the press about a toxic work environment, when all I’ve ever heard from every guest that comes on the show is what a happy atmosphere this is and what a happy place it is.”

Confirming the decision to end the show, DeGeneres said in an interview with The Hollywood Reporter that she was moving on because the programme was “just not a challenge anymore”.

According to the publication, she had been considering the move for several years and informed staff of her decision on 11 May.

However, it comes following the controversy in 2020, which led to DeGeneres apologising to staff after an internal review by Warner Bros found “deficiencies related to the show’s day-to-day management”.

The show returned, but ratings have reportedly taken a hit. Data from audience counter Nielsen shows The Ellen DeGeneres Show viewership dropped by 1.1 million people this season, from 2.6 million viewers to 1.5 million.

DeGeneres told The Hollywood Reporter that the claims were “very hurtful” but that she was not quitting the programme because of them.

“If I was quitting the show because of that, I wouldn’t have come back this season,” she said.

In her opening monologue for her latest show, which was recorded on Wednesday, an emotional DeGeneres revealed more about why she was ending the programme.

“You may wonder why I’ve decided to end after 19 seasons,” she said. “The truth is, I always trust my instincts. My instinct told me it’s time. As a comedian, I’ve always understood the importance of… timing.

“In all seriousness, I truly have felt like next season was the right time to end this amazing chapter.”

The show has received 171 Daytime Emmy Award nominations and won 61 Daytime Emmy Awards.

DeGeneres’ departure coincides with the end of her contract.