Chantelois told New Idea that one incident happened after the Premier had asked her to his office.
When I got there, he grabbed me and pinned me against the door and began kissing me with his tongue, she told said.
Then he guided me to his desk and sat me on top of his desk and dropped his trousers and had sex with me. It was mutual and I was not surprised.
Ms Chantelois also detailed late-night encounters at a city golf course.
"We would go parking ... it was always late in the evening, dark, no one could see us," she said.
The South Australian Prime Minister continues to maintain the allegations were false. only designed to do him damage, both personally and politically.
He said the claims were totally false and were only aimed at damaging him politically and personally.
"There were suggestions that I had sex on the floor of Parliament House, in my office, between meetings while parliament was sitting," he said.
"Any one of you who is a political reporter would know how absolutely ridiculous and absurd that would be.
"My office is like a train station, a revolving door on grand central station.
"I am constantly surrounded by advisers, members of Parliament come in and out, ministers come in and out, staffers come in and out, members of the Opposition come in and out.
"The suggestion that I would have sex on a golf course in Adelaide, as a fairly visible citizen of this state, is totally, absolutely ridiculous.
"So I reject these allegations and I can say today that I will be taking legal action against Channel 7 and New Idea for allegations that are totally, absolutely untrue."
Asked if he had ever had sex with Ms Chantelois at any place, Mr Rann said he had "rejected those allegations of having sex with her".
"I have not had sex with her," he said.
Mr Rann said his friendship with Mrs Chantelois was "flirty" and "based of confidences".
"I've never hidden the fact that I had a friendship, but there's a real difference between that friendship and what has been said," Mr Rann said.
Mr Rann said his wife Sasha Carruozzo, who he married in 2006, was fully aware of his previous friendship with Ms Chantelois.
"If Sasha is comfortable with my friendships, then why should anybody else in the state not be comfortable," he said.
Chantellois herself claims her secret affair destroyed her 15 year marriage, broke up her family and left her on the brink of suicide. Her husband, Rick Wayne Phillips, an Adelaide businessman was charged with assaulting Mr Rann last month.
It was then reported that he was struck repeatedly in the face during a "brutal" bashing at a corporate dinner.
The Premier said he was "fine" after the man allegedly hit him in the face up to six times with a rolled-up magazine in Adelaide last night.
Mr Rann was allegedly attacked from behind while seated at a table at the $600-a-head business function.
The 55-year-old Phillips has been charged with aggravated assault. He will appear in court in December.
Source-Medindia
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