Treasurer Troy Buswell has settled his defamation case against former lover and former Greens MP Adele Carles.
Mr Buswell's lawyer Martin Bennett said yesterday that the lawsuit had been settled by an agreement formalised this week.
The out-of-court settlement allows the former couple to avoid a likely long trial, which would potentially have aired intimate details about their relationship and break-up.
Mr Bennett said the agreement included Ms Carles providing Mr Buswell with a written apology.
Mr Buswell launched his legal action in December 2012, alleging Ms Carles had defamed him across a range of media outlets by making comments about his state of mind, drinking and behaviour at the home of Perth businessman Nigel Satterley at a party about a year earlier.
Mr Buswell, whose case was subsequently expanded to include comments made by Ms Carles at a news conference, denied the claims about his behaviour.
In her unreserved apology, Ms Carles accepts that comments she made between December 2012 and January last year at a news conference, on radio, via Twitter and through her communication with journalists contained defamatory allegations.
"I sincerely apologise for the damage, distress and embarrassment that I have caused Mr Buswell," she said. As part of the settlement, Ms Carles has also apologised to Mr Satterley and agreed not to pursue separate action against him.
She has also given a written apology to seafood magnate Nick Kailis, who she claimed had been on the receiving end of Mr Buswell's alleged behaviour at the December 2011 party.
Ms Carles also apologised to banker Andrew Whitechurch, whom she named as a witness to the alleged incident. Ms Carles has also provided mining magnate Chris Ellison with a written apology.
In a radio interview in December 2012, Ms Carles made allegations about Mr Buswell's behaviour during a second and unrelated incident at the millionaire's home the previous March.
Mr Bennett said Mr Buswell did not want to comment on the confidential settlement.
Ms Carles could not be contacted yesterday.