Chelsea Handler has admitted she "wasn't respectful" to Joan Rivers and didn't give the late comic the "the kudos she deserved".
The pair fell out prior to Joan's death in 2014 with Chelsea revealing their feud started because she had "kinda blown her off" when she was "young and arrogant".
Opening up about the bad blood between the pair, Chelsea explained herself during a chat with Joan's daughter Melissa on the 'Melissa Rivers' Group Text Podcast'.
Chelsea said: "Your mom approached me a couple times when we were on E! I just felt like a s*** because I had just kinda blown her off. I wasn't respectful in the way I realise I needed to be now."
The 'Chelsea Lately' star was among those who paid tribute to Joan in Netflix special 'The Hall: Honoring the Greats of Stand-Up' and Melissa was furious when she found out about the tribute from Chelsea.
Melissa told the TV host she "went f****** bananas" when she was told Chelsea would be honouring Joan, prompting the comedian to explain why she did it.
Chelsea said: "(I was) so excited about the opportunity to do it, to go and say those things in front of everybody. To be like, you have to remember that every opportunity that anyone has in this world as a female comedian, you have to thank the people who came before you."
She added: "When I was on E!, I was so young and arrogant and just thought, 'I did it. I got myself to where I was.' I didn't give her the kudos she deserved and so I was eager to like put that in writing."
The comedy special debuted in May and during the show Chelsea admitted Joan actually had a huge impact on her career.
She said: "The first time I meet Joan Rivers, we were both on E! - and not the fun kind. It was the basic cable network with the exclamation point, which in hindsight was still a good time.
"But, at the time though, I did not realise the enormous impact Joan had on my career."
Chelsea went on to say: "I was too wrapped up in my own world. I was too young, too confident, and too arrogant to believe anyone had a hand in my success but myself. Now, I know that for every success I've had it was because someone came before me who was bolder and braver and good luck finding someone else who was as bold and as brave as Joan Rivers."
Joan died on September 4 2014 at the age of 81 after suffering complications during surgery on her throat.