SENATOR Ivor Callely has defended his €87,000 mileage bill while serving at the Department of Health, saying it was no different to any other junior minister.

Callely, who last week resigned from the Fianna Fáil party, insisted that all of the travel related to his ministerial duties and did not include his personal mileage.

The embattled senator said he had purchased the ministerial car involved, maintained it, paid for its tax and insurance and all other costs associated with it.

Last week, the Sunday Tribune reported how Callely routinely claimed 5,000 miles every month during his time as a junior minister at the Department of Health.

In one single month when he spent seven days in America, he still managed to claim the maximum mileage – the equivalent of a round trip to Belfast every single day, including Saturdays, Sundays and Bank Holidays.

However, in a legal letter sent to the Sunday Tribune, Callely's legal representatives said that the article was "misleading" and created an "innuendo [that] is entirely and totally false". It said that the article "exposes [Ivor Callely] to odium, ridicule and contempt".

The letter said: "The mileage in question related to [a] ministerial car and this mileage amounted to a substantial number of miles unrelated to the personal mileage incurred by Senator Callely on his travelling to and from his office.

"In addition, the ministerial car was not provided by the department. Our client purchased the car in question, he maintained the car, had the responsibility for maintenance, servicing, insurance and tax and would have suffered any devaluation of the car in question.

"His position is in line with that of other junior ministers and the fact that the Sunday Tribune singled him out for particular treatment implied that our said client acted in a manner which was deviant and totally different to that of his colleagues."

Callely also insisted that the mileage claims were not unique and that the money paid out was "in line with that" of other ministers.

However, the evidence does not back up his assertion. Earlier this year, European Affairs Minister Dick Roche was questioned about €50,000 worth of mileage claims he made in 2008 and 2009.

The Department of Foreign Affairs said that in both years, Roche had been heavily involved in campaigning for the Lisbon Treaty and had travelled all around Ireland as part of that work.

Even at that, Roche's €25,000 annual expenses were substantially lower than the €40,330 claimed each year by Callely.

In 2007, details of junior ministerial travel expenses were also released to Fine Gael TD Leo Varadkar by a number of government departments.

They showed that another Dublin minister, Noel Ahern, ran up mileage expenses of €19,710 in 2006, substantially lower than what Callely had been paid several years earlier.

Junior ministers were allowed to claim expenses following a government decision in 1983, which disallowed access to a state car.

They were instead given a civilian driver – but told they would have to pay for the costs of their own car, with claims topped at 60,000 miles each year.

Callely has also said that all other expenses paid on his behalf while at the Department of Health were on foot of arrangements made by civil servants.

In all, the senator's expense claims during 26 months as a junior minister came to €123,221, which included a €5,000 limousine bill in the US, VIP lounges and a bash at Fadó restaurant for 25 people costing €2,257.

Callely also took issue with this and the legal letter said: "There are other allegations... which imply that our client manipulated and deliberately used his position inappropriately and deliberately to his own advantage when in fact all such ministerial activity is arranged by the relevant civil servants in the relevant department similar to that of any other minister.

"Accordingly the implication in your article was that our client acted deliberately and in a manner different to other ministers in a similar position."

Callely's political future was in doubt this weekend with the senator facing calls to resign following his departure from Fianna Fáil.

A number of government representatives including ministers Seán Haughey and John Gormley have asked him to step down, while Defence Minister Tony Killeen said it would be better for politics if he stood down.

Other ministers have been more circumspect with Mary Hanafin saying that the Senate Committee investigating his expense claims should be left to do their work.

The controversy over Callely's ministerial expense claims is just the latest in a long line of revelations about the Dublin politician.

Already under investigation have been his mileage claims from a holiday home in Co Cork and receipts for the purchase of mobile phones that were submitted on official paper from a company that had gone out of business.