The role of public interest directors at banks in which the state is a shareholder is flawed according to former finance minister and Permanent TSB (PTSB) public interest director Ray MacSharry.

Appearing before the Oireachtas Committee on Finance, Public Expenditure and Reform Mr MacSharry accepted that the role should enable a distinct line of communication to the Minister For Finance.

Earlier Fianna Fáíl finance spokesman Michael McGrath had put it to Mr McSharry that there was "a flaw in the structure of the role of public interest directors that they didn't have any distinguishing feature such as a distinct line of communication to the Minister".

Mr MacSharry said this was "absolutely right". "We don't have the ability to come out of a board meeting and make points," he said.

The role of public interest directors was limited to trying to "influence rather than dictate" policy to the bank's board of directors, according to Mr MacSharry.

Asked by committee chairman Ciaran Lynch if had voted against the board in his capacity of public interest director, Mr MacSharry said at all times he took into account the interests of the stakeholders which included the customers.

He said he had his views representing the public had never been pushed to a vote.

The bank's other public interest director, Margaret Hayes, told the commitee PTSB was working "assiduously to address its growing mortgage arrears problem.

PTSB has 174,000 mortgages, she said, of which some 20% of its homeloans were in arrears of some description. Ms Hayes said she was confident that the bank would improve the arrears situation.