The Irish police force (Gardai) have confirmed they will send their file on alleged financial irregularities at Anglo Irish Bank to the Irish Director of Public Prosecutions by the end of the year.

Detectives from the garda fraud bureau and staff from the Office of the Director of Corporate Enforcement have confirmed their investigation has entered its final phase.

Meanwhile officers are in negotiations with the legal representatives of former Anglo chief executive David Drumm, who is now the only key Irish banker still to be interviewed.

It is hoped that Drumm will make himself available voluntarily for interview in Ireland when he returns to Dublin from his new home in the U.S. for civil proceedings in the courts.

In Dublin detectives are currently carrying out in depth interviews with  three former senior figures in Irish Life and Permanent (IL&P) about controversial transactions.

The investigators had been anxious to get an account from the three IL&P executives to establish what they knew about the deposits that falsely altered the bank's financial status in the lead-up to the collapse.

Fraud bureau detectives are focusing on the movement of 7.45 billion euro in deposits between Anglo and IL&P to bolster Anglo's books and the loan of 450 million to the so-called 'Maple 10,' a golden circle of 10 Irish investors, to buy bank shares.

Gardai have taken around 350 statements and are sifting through over 100,000 emails and transcripts of telephone calls as they attempt to unravel the complex transactions in the lead up to the collapse.