FIANNA Fáil TD John O'Donoghue has threatened to sue Ryanair after a series of newspaper ads lampooning his political expenses.

O'Donoghue, who was forced to step down as ceann comhairle last year amid controversy over his overseas travel costs, described the advertisements as a "black lie".

The Ryanair ad said that John "Expenses" O'Don-oghue had thought nothing of spending taxpayers' money on first-class airfares, five-star hotels and limousines between airport terminals.

The advert, printed in local newspapers, came in response to an online petition organised by the Kerry TD against a reduction in service by the airline on the route between Dublin and his home county.

Ryanair's Stephen McNamara said: "If John O'Donoghue and Noel Dempsey [Minister for Transport] had wasted less money on their planes, trains and limousines in recent years, the Department of Transport could afford the €440,000 required to preserve Ryanair's three daily return flights on the Kerry to Dublin public service obligation [PSO] service.

"[It] will be cut to one daily return flight from next week, and the people of Kerry would have [had] their PSO service instead of a useless internet petition on the even more useless Fianna Fáil website."

According to an interview in Kerry's Eye newspaper, O'Donoghue is now considering legal action in response to the newspaper advertisements.

He said: "It is a black lie and confirms the claim made by Mr Justice Kelly in the High Court recently that Ryanair and the truth make for uneasy bedfellows.

"The ad is diversionary, it is a smokescreen and it is a red herring. Michael O'Leary may be attempting to hoodwink the people of Kerry – but we are no fools in Kerry."

O'Donoghue accused the airline of a "greed and disregard for the people of Kerry".