Most political parties in Ireland were involved in polling that saw volunteers pose as independent pollsters, according to Minister for Foreign Affairs Simon Coveney.
The Fine Gael politician also said he was aware that members of his constituency posed as independent pollsters, the Irish Examiner reports.
Fine Gael, Fianna Fáil, the Green Party and Sinn Féin have all admitted that their party members previously polled the public during elections while hiding the fact they worked for a political party.
“I think it exposes something that most political parties in Ireland were involved in up until five, six, seven years ago,” Mr Coveney said.
“In my constituency certainly there were members would have been doing survey work in the constituency. Taking polling data.
“We didn't set up a fake company or anything but I mean, there would have been people doing survey work in the constituency and not saying they were Fine Gael.”
Mr Coveney said he was sorry about the practice but added it was stopped a “long time ago”.
He said it became clear it wasn't the “professional way to do things” and politics was “looser” then.
“I think it's important that people put their hands up and say that, that shouldn't have happened. It doesn't happen anymore. Polling is now done by professional polling agencies and organisations,” he said.
When it was put to Mr Coveney that his own colleague Simon Harris said that Sinn Féin’s use of the practice was “sinister”, he said that he had been in politics longer than Mr Harris.
“I mean, most of this activity happened, six, seven years ago,” Mr Coveney said, but did not acknowledge that Mr Harris had been in politics for over ten years.
It comes after the Taoiseach, Fianna Fáil leader Micheál Martin, said the practice of political party volunteers posing as pollsters should not have happened.
Mr Martin told Newstalk Breakfast that it was not right, not proper and should not have happened.
Prior to 2007, members of Fianna Fáil were used to supplement polling companies who oversaw the polling exercise, he said.
When asked if the party had broken the law by doing this, Mr Martin said he did not know.
No personal data had been taken or recorded, he said, and no fake IDs had been used by the party activists.
In a statement on Wednesday, Fianna Fáil confirmed party activists posed as market researchers before 2007 while carrying out polling.
The news followed an article in the Irish Independent on Wednesday which reported Sinn Féin issued ID badges to party activists with the name of a market research company, Irish Market Research Agency, which does not exist.
Sinn Féin admitted the practice, while Fine Gael leader Leo Varadkar said his party had engaged in “similar” practices before 2016.
Mr Varadkar admitted his party paid students to misrepresent themselves as pollsters in order to carry out covert surveys of voters. He said the “practice has been discontinued” since 2016. Earlier, he said Fine Gael has only used private polling companies since he became party leader.
Earlier on Thursday, the Green Party said there may have been “isolated incidents” where it used party volunteers to carry out polling using a false company name. On Wednesday the party said it had never engaged in such practices.
Political parties will have to reveal to the Data Protection Commissioner if they are processing personal data gathered during polling, where practices such as party activists posing as pollsters may have been used.
A spokesman for the Labour Party has said it has not engaged in similar activity and “our head office wouldn’t sanction such an approach”.
A spokeswoman for the Social Democrats has said it has “never engaged in posing as independent market researchers or opinion poll companies to survey voters”.