Siptu, the State's biggest trade union, has refused to comply with the accounting standard FRS17 in its latest annual accounts. It claimed yesterday FRS17 was an "inappropriate accounting standard" that was detrimental to defined-benefit pension schemes.

Siptu has a defined-benefit scheme for its 300 staff.

FRS17 is a global accounting standard that requires organisations to recognise pension surpluses or deficits on their balance sheets on a current-day basis.

Siptu's accounts, to be formally registered today with the Registrar of Friendly Societies, show the union generated income of €36.9 million in 2005.

Siptu general secretary Joe O'Flynn said this was a "reasonably good" financial performance, pointing out that Siptu was not a profit-making organisation.

But he said the union had "once again" refused to comply with FRS17 and would keep doing so as long as it remained in its present form. Firms are obliged to file accounts using FRS17.

"If the standard had been applied in our case, our net assets would have been significantly reduced because of the deficit in our staff pension fund," he said.

"This would be misleading on a number of counts, not least because the union, in conjunction with its staff and with the approval of the Pensions Board, has put in place a financing plan which will eliminate the deficit over an extended time span without compromising the integrity of the scheme."