The paedophile was heard making suggestive comments to young girls he met, sometimes in front of their parents, and later bounced girls on his knee.
Although the Jim'll Fix It star was a regular visitor here throughout his career, this is the first time an eyewitness has come forward to allege unsavoury behaviour by the notorious DJ while in Ireland.
The account is from RTE's former head of entertainment David Blake Knox, who was paid by a friend in PR to spend a day with Savile while he attended a charity event in Ireland in the 1970s.
"My abiding memory of Jimmy Savile is that he talked about sex the whole time. I was actually quite shocked because I wasn't used to hearing adults talking about sex as crudely as he did. The way he talked about young women was shocking. I remember him making suggestive comments to young girls sometimes in front of their parents, and even priests," Mr Blake Knox told the Herald.
While the 59-year-old did not see Savile molesting any girls, he felt uncomfortable in Savile's company.
"His behaviour around them (girls) was creepy, suggestive and inappropriate. He would put his arm around them, and cosy up to them."
Mr Blake Knox said that the function, which took place in a marquee after a fun-run, was not connected to the Central Remedial Clinic who invited Savile to lead fundraising walks for the Central Remedial Clinic from 1968-1981. He said his abiding memory of the day is the sycophancy shown to Savile by all who met him.
"People fawned around him and were almost reverential in the way they reacted to him. I thought he was a lech but never realised he was a criminal and into underage sex," said Mr Blake Knox.
The Central Remedial Clinic has previously said that it was unaware of any allegations about Savile during or after his involvement with the charity, and that at no time had the TV presenter been left unattended with children in its care during his visits to Ireland.