The Department of Finance is confident it will recover "almost all" its investment in the country's viable banks, according to its Secretary General. 

Derek Moran is before the Public Accounts Committee today to discuss the Department's expenditure last year. 

In his opening statement, Mr Moran said investment by the Irish taxpayer in the banks has been "unprecedented", totalling over €64 billion. 

That investment comprised €34.7 billion in the Irish Bank Resolution Corporation and €29.4 billion into the viable banks - AIB, Bank of Ireland and Permanent TSB. 

Based on latest valuations, Mr Moran said the total current value of the State's investments in the three remaining banks is €18 billion.

Meanwhile, officials from the Department of Finance have said it will take time to understand reasons for the increase in corporate tax intake this year. 

Independent Alliance TD Shane Ross asked the reason for the "spike in profits". 

Secretary General Derek Moran said there were a range of explanations such as improved trading conditions, recovery in the US and UK economies and more companies paying tax as they come out of recession. 

He said the Department is blind to the details of tax returns by corporates until the the year, adding that Revenue has a unit that deals directly with multinationals. 

"It will take time to drill down into this. We've to understand what has happened and what lies behind it..", he said. 

The Department's chief economist John McCarthy also noted that more smaller companies are paying tax this year compared to last year because many had come into profit. 

He echoed the Secretary General in relation to the depreciation of the euro improving profitability for many US companies. 

Mr McCarthy also said officials at the Department were "surprised at the momentum" of growth.