“It was 2 in the morning and I was Ambien tweeting-it was memorial day too-i went 2 far & do not want it defended-it was egregious Indefensible,” she wrote. “I made a mistake I wish I hadn’t but … don’t defend it please.”

In other tweets, Barr said that she was tired of “being attacked and belittled more than other comedians who have said worse” and asked for people not to boycott ABC, saying that the network has the right to “do what they wish”.

Walt Disney Co’s ABC network on Tuesday cancelled her popular US television comedy Roseanne after her tweet.

“Roseanne’s Twitter statement is abhorrent, repugnant and inconsistent with our values, and we have decided to cancel her show,” ABC Entertainment President Channing Dungey said in a statement.

Barr, 65, then apologised “for making a bad joke” about Jarrett, who is black and was born in Iran to American parents.

“Don’t feel sorry for me, guys!!,” Barr said in a tweet late on Tuesday. “I just want to apologise to the hundreds of people, and wonderful writers [all liberal] and talented actors who lost their jobs on my show due to my stupid tweet.”

Jarrett, 61, said on Tuesday that Disney CEO Bob Iger called her before ABC announced the show’s cancellation.

Iger tweeted, “There was only one thing to do here and that was the right thing.”

Jarrett, during an appearance on an MSNBC town hall on Tuesday, said: “I think we have to turn it into a teaching moment.”

“I’m fine,” she continued. “I’m worried about all the people out there who don’t have a circle of friends and followers who come right to their defence – the person who’s walking down the street minding their own business and they see somebody cling to their purse or walk across the street. Or every black parent I know who has a boy who has to sit down and have a conversation, ‘the talk’ as we call it. Those ordinary examples of racism that happen every single day.”

Before Barr apologised on Twitter, she also exchanged tweets with Chelsea Clinton, the daughter of former President Bill Clinton, after Barr referred to her as “Chelsea Soros Clinton”, a reference to George Soros, the billionaire liberal donor who is often the focus of conservative critics.

When Clinton corrected Barr and added that she imagined the Soroses were “lovely people”, Barr responded by calling Soros a Nazi.

Emmy award winner Rosanne Barr slams Lorde as a 'bigot' over Israel

Hollywood talent agency ICM said in a statement on Tuesday it will no longer represent Barr. Several networks said it was removing reruns of her show. Hulu said episodes of the new show would no longer be available on its streaming service.

The original sitcom Roseanne ran from 1988 to 1997, featuring a blue-collar family, the Conners, with overweight parents struggling to get by. It was praised for its realistic portrayal of working-class life.

The current version was ABC’s biggest hit of the 2017-2018 season, drawing an average 18.7 million viewers, second only to CBS sitcom The Big Bang Theory, according to Nielsen data through May 20.

But the reboot was parked firmly in Trump territory, with the fictional Roseanne – as in real life – an ardent supporter of the 45th US president.

President Donald Trump has latched onto the show’s huge viewership as evidence that his supporters want shows that speak to their concerns.

Before the statement from Dungey, the black comic Wanda Sykes, who was a consulting producer on the revived Roseanne show, tweeted that she would not return to the series.

And Sara Gilbert, a member of the cast, took to Twitter to say that “Roseanne’s recent comments about Valerie Jarrett, and so much more, are abhorrent and do not reflect the beliefs of our cast and crew or anyone associated with our show. I am disappointed in her actions to say the least.”

Additional reporting by Associated Press