Anglo Irish Bank chief executive Mike Aynsley last night pledged to actively pursue David Drumm to get back as much money as possible for the taxpayer.
Mr Aynsley told guests at the launch of a book about Anglo that his predecessor, who now lives in Boston, "needs to get a bit of back-bone and come back" to face the Irish public.
He said the investigation into the bank would take time as there were millions of documents to go through.
Earlier, Justice Minister Alan Shatter voiced his disappointment at the refusal of Mr Drumm to co-operate with investigations by the garda fraud bureau into financial irregularities during his tenure at Anglo.
He was commenting on yesterday's Irish Independent report, which revealed that the gardai had decided to complete their file for the DPP without interviewing Mr Drumm, who has ignored repeated requests to meet officers. The file will be on the desk of the DPP within a month.
Mr Shatter said: "It is disappointing that he didn't co-operate. People will draw their own conclusions.
"Here we have an individual who has taken off to the United States and who is clearly not co-operating.''
If the DPP determines that the file contains sufficient information to warrant a prosecution against Mr Drumm, gardai could seek an extradition warrant.