Published Sunday, 23 March 2014
Patrick Nulty has quit over the revelations. (© PA)
Patrick Nulty, who represented Dublin West, claimed to have been "under the influence of alcohol" when he contacted the 17-year-old.
His resignation was announced in a statement released just hours before details of the story were due to be published in Sunday World.
Mr Nulty said: "I sent inappropriate messages via Facebook. This included inadvertently sending one to a 17-year-old woman. To the best of my knowledge I have never met this woman and the message was sent while under the influence of alcohol."
According to the Irish tabloid, 31-year-old Mr Nulty asked a schoolgirl in a late night Facebook message: "Have you ever been spanked?"
It is further alleged that a woman was asked to send underwear in the post and another was urged to wear a skirt when visiting a constituency clinic.
His statement continued: "It was never my intention to upset anyone in this way but it was totally wrong. I set myself the highest standards personally and politically.
"Unfortunately due to personal mistakes I have not met those standards in this matter and I will take responsibility for that.
"In politics people very often do not take responsibility for their actions. I hope I am doing that. I would further like to apologise to my constituents in Dublin West for my mistake.
"I hope they will understand my reasons for resigning and accept my apology.
"I hope that as I have taken decisive and direct action on this matter my privacy will now be respected in what has been a very difficult decision for me personally."
© UTV News