Justice Minister Dermot Ahern said he had no role in determining when a garda file into the Anglo Irish Bank probe would be sent to the Director of Public Prosecutions (DPP).
Fine Gael said the pace of the investigation was in stark contrast to probes in the United States, where almost 50 prosecutions into financial wrongdoing had been secured.
Finance spokesman Michael Noonan challenged Mr Ahern to publicly reveal when the Garda file would be passed on to the DPP.
"Why are we still waiting for the Garda file on the Anglo investigation to be sent to the DPP?" he asked.
"Elsewhere there has been swift action to deal with criminal wrongdoing but here we are, nearly two years into the crisis that has crippled our economy, and there is still no sign of any prosecution being brought forward.
"It is an increasing concern of mine that there simply isn't a political will within this Fianna Fail administration to see these types of issues brought to a head."
But Mr Ahern said Mr Noonan knew Ministers for Justice had no role in garda investigations.
"That is the norm in parliamentary democracies and it is alarming that Fine Gael are now suggesting that we depart from that," he said.
"Any person guilty of fraud or financial misconduct will be brought to justice as soon as possible. But we cannot permit political interference in policing or the independent prosecution system."