It has emerged that the Transport Minister used the government jet to travel to Donegal to address the MacGill Summer School in Glenties last month.
Noel Dempsey, who flew into to Derry, addressed the school on 'reforming the republic' at a cost to the tax payer estimated at one hundred thousand euro.
The transport minister used the state's 'Gulfstream IV' jet for the journey from Dublin to Derry to attend the MacGill Summer school on July 19th.
A garda driver had also been dispatched from Dublin to Derry to collect the Minister and take him across the border into Donegal.
The jet waited overnight for Minister Dempsey in Derry as the next day, after his speech to the school, he had to travel to Dublin for 'urgent government business'.
It costs the state almost 8 thousand euro an hour to keep the jet in the air and 4,000 euro on the ground, these figures have been used to estimate a 100,000 euro bill to the tax payer for the Minister's address to the MacGill Summer School last month.