An emotional Jackie O has apologised to Parramatta Eels skipper Kieran Foran at the start of her breakfast radio show on Friday morning for comments she made last week that she now recognises were "ugly", "insensitive" and "really stupid".

The KISS 1065 host's voice wavered as she directly apologised to Foran and his former partner, Rebecca Pope, after she referred to rumours on the show last Friday questioning the paternity of the couple's second child.

McGirr Lawyers, the legal firm acting for Foran, had begun legal proceedings against the Australian Radio Network, sending a concerns notice to management demanding an on-air apology on Friday's breakfast show.

Jackie O made the apology as soon as the Kyle and Jackie O Show went to air just after 6am on Friday.

"I gave voice to really ugly rumours and I just wanted to apologise for that, because it was stupid to say what I said, and it was really insensitive, especially considering what Kieran's going through at this time in his life," Jackie O said.

Foran, who recently split from Ms Pope, is in a rehabilitation facility after overdosing on prescription medication last week. He has been granted indefinite leave of absence from the Eels following the incident.

Jackie O said she would not repeat the "ugly rumour" she referred to on last week's show, and said she felt terrible about the comments she had made.

"I just want to take this time to personally apologise to Rebecca and Kieran for what I said. I can imagine how hurtful that would have been and I feel really terrible, I really do, and I'm truly sorry," she said.

"Despite what some people might think, it's not what I'm about in radio, and I have tried very hard in my career not to be hurtful, and that's why I'm very sorry for any harm that I've caused and I hope that they will accept my apology. I am sorry," she said, her voice wavering.

The apology would be re-played on air later in the morning, she said.

Her radio co-host, Kyle Sandilands, said he had no idea what the controversy was about.

"Well that's nice. I don't really know, I've just got here, so I have got no clue what's going on ... I've got no idea what that's all about, but it sounds quite legally involved," he said.

"It looks like you're in the shit, and better you than me, because this is usually something that I'm asked to do and I ... refuse to ever do anything. I never say sorry about anything, ever."