Jones said he had tried to contact Ms Gillard to apologise in person, but had so far not been able to make contact.
He was speaking after being recorded making the comments about John Gillard at a Sydney University Liberal Club function, leading to widespread condemnation today, including calls for advertisers to boycott 2GB.
"Every person in the caucus of the Labor Party knows that Julia Gillard is a liar,'' News Limited reported Jones as saying at last Saturday's event.
"The old man recently died a few weeks ago of shame. To think that he had a daughter who told lies every time she stood for parliament.''
Mr Gillard died aged 83 on September 8 after a short illness.
Jones said he had repeated comments he heard prior to the Liberal function, at a birthday party for his goddaughter in the NSW Hunter Valley.
"To repeat them was wrong, to even offer any impression that I might seek to diminish the grief a daughter would feel for her father, independently of who that daughter might be, is unacceptable.''
He insisted he had not been drinking during the event and had spoken off the cuff.
He also said he thought the function was a private event and the speech off the record.
A News Ltd reporter recorded the comments, which were subsequently reported on today.
Jones said he would not refrain from criticising Ms Gillard and her policies.
"I don't dislike the prime minister, I dislike her policies,'' he said.
Jones also dismissed the possibility of 2GB losing sponsorship and advertising revenue over the matter, saying it was a matter for the station.
A spokesman for Ms Gillard today said the prime minister did not intend to speak to Jones about his comments.
Ms Gillard is in Sydney where she is attending the NRL Grand Final.
-AAP
