Denis O’Brien has initiated legal proceedings against the former Fianna Fáil TD for Galway East Colm Keaveney.

Mr O’Brien is suing Mr Keaveney for defamation arising from the proposed text of a speech by the politician that was circulated to a public relations company, Red Flag.

Mr O’Brien has been separately embroiled in legal proceedings against Red Flag and some of its senior staff, including founder Karl Brophy.

The speech document, which included numerous references to Mr O’Brien and the results of the Moriarty tribunal, contained material that the businessman’s lawyers allege was defamatory and damaging to his reputation.

Mr O’Brien issued proceedings on Tuesday against Mr Keaveney, who lost his seat in the recent general election.

Through his lawyers, Eames, Mr O’Brien had previously sought an apology from Mr Keaveney over the allegedly defamatory material.

Eames wrote to the politician in March seeking an apology published in two national newspapers and one international publication.

Accused

The letter from Eames accused Mr Keaveney of having a “a malicious intent on your part to harm” Mr O’Brien by sending material to Red Flag.

It is understood Mr Keaveney declined to apologise to the billionaire, who then issued proceedings.

Papers have not yet been served on the politician, who declined to comment.

A spokesman for Mr O’Brien made no response to a message seeking comment.

Separately, Mr Keaveney is also suing Independent News & Media, where Mr O’Brien is the largest shareholder, for alleged defamation.

He alleges that an infographic accompanying a news story suggested he was part of a conspiracy to damage Mr O’Brien.