A report by the State's spending watchdog found more than €4 million of public funds was paid into an unofficial Siptu bank account which was used to finance foreign trips for public officials and trade union figures.

The Comptroller and Auditor General's report said a range of state bodies paid money into the controversial bank account – the Siptu National Health and Local Authority Levy fund - between 2002 and 2009.

However, the bulk of the money emanated from the Department of Health, the report found.

A senior Siptu official was identified on bank documentation as trustee of the account, and acted as fund administrator until 2010.

The comptroller’s investigation found that employees of public bodies engaged in an unpsecified number of foreign trips that were arranged and paid for from the fund.

It concluded that such arrangements were “inappropriate” and “bypassed internal controls” over the charging of and accountability for foreign travel expenditure incurred by public employees.

The report said the provision of public money to the fund came via a complex chain of funding transfers.

“There was no effective oversight or formal accountability for the fund’s operations,” it concluded.

The report also found the balance of the fund consistently “well in excess” of the immediate requirements for fund-based activities.

In five of the seven years between 2002 and 2008, substantial grant payments were made by public bodies in December.

“ In effect, the fund may have acted as a mechanism for public bodies to avoid unused money allocated for partnership purposes being surrendered back to the exchequer at year-end,” it said.

About €2.2 million was paid out of the fund account on training programmes and grants, with a further €1 million in unused funds returned to state bodies between late 2010 and December 2012.

It estimated that the net cost to taxpayers of the fund’s operations since 2002 was of the order of €3.15 million.

Siptu said today it accepted the report’s findings and that they were consistent with the findings of its own internal investigation.