TAOISEACH Enda Kenny says the State's justice authorities are right to take their time in pursuing prosecutions against bankers.
Mr Kenny said people were angry and frustrated about the lack of cases in court to date, before adding: "It's absolutely critical that they get it right."
The Taoiseach also said he wanted the planned banking inquiry to cover the last 10 years.
Mr Kenny said the public were "frustrated" with the delay in prosecutions, but he wasn't being critical of the handling of the process by the Director of Public Prosecutions.
"I think there is always a wariness about rushing into something here. If you make a wrong statement, a wrong comment, prejudice a case and whatever else, and particularly cases like this, where they are very technical and very complex, it's absolutely critical that they get it right," he said.
Mr Kenny said the Government has supported the authorities investigating the banking system.
"I like to see the system operate properly, independently and effectively and it will make its own decisions in its own way," he said.
Mr Kenny said the issue of parliamentary inquiry is separate to any banking investigations.
"There is a need for the political system to be able to work in the background, which lead to all these decision, to understand the nature and the environment of who did what and why, which lead to these decisions being taken, which hoisted the biggest economic burden ever on the backs of the Irish people," he said.
Mr Kenny said the parliamentary inquiry needed to look back at what happened over a number of years.
"While (previous inquiry) Nyberg, for instance, was entitled to go back a lot further than it did, it chose not to do so.
"But I think there is a need here to understand how the system got sucked into the false comfort of dealing with a bloated construction sector, as if it would continue forever, and that as a consequence banks and everyone else became entwined in all of that," he said.
"I want them to go back six, eight, 10 years," he said.