SINN Fein deputy leader Mary Lou McDonald has been accused of causing a loss of almost €130,000 to the exchequer following her controversial decision to shut down the Dail for over four hours last week.
It was claimed last night that Ms McDonald's actions, which have been dubbed an "outrageous stunt", will result in the Dail's schedule being altered in order to accommodate a debate on social welfare.
The Dublin Central TD has been widely criticised after she refused to leave the chamber last Thursday despite a vote by TDs to suspend her.
The government parties as well as members of the Opposition believe the sit-in was designed to deflect attention away from Sinn Fein's treatment of Mairia Cahill and the IRA sex abuse scandal.
The political row is set to escalate today after Labour claimed Ms McDonald's actions have cost the taxpayer almost €130,000.
The bill for running the Houses of the Oireachtas last year came to a total of €101m.
This overall sum includes the combined costs of running the Dail, Seanad and Committee business. The party said that on this basis, it calculates that Ms McDonald's decision to bring the Dail to a halt for four and a half hours cost the taxpayer an estimated €129,040.
Cork South West TD Michael McCarthy said the analysis carried out by the party illustrates the high cost of Ms McDonald's "outrageous" exercise.
"Mary Lou's outrageous stunt cost the Exchequer €130,000 by shutting the Dail down and forcing it to reschedule vital business until Tuesday," he said.
"By crudely sabotaging the important work of our national parliament, she not only held up a Dail debate on increasing child benefit, but also cost the Exchequer a huge amount in lost sitting hours, which now have to be made up," he added.
Sinn Fein will today discuss the fallout from Ms McDonald's Dail sit-in.
The party is embroiled in a bitter war of words with Ceann Comhairle Sean Barrett after he followed Dail procedure and suspended Ms McDonald.
Party leader Gerry Adams has said he has no confidence in Mr Barrett - a claim that his opponents believe is disrespectful to the institutions of the Oireachtas.