The regulator for pension funds, the Pensions Board, has been swamped with requests for assistance from trustees seeking to cut benefits to keep their underfunded retirement schemes from becoming insolvent, in a sign that the pensions crisis is deepening.

More than 25% of pension funds are considering reducing their pay-outs to retirees in order to keep from going bust and have inundated the Pensions Board with requests for meetings to help guide them through the process.

However, the board has warned trustees that the volume of enquiries means it will not be able to grant all the requests, leaving the funds to fend for themselves, even though changes to benefits require approval.

In lieu of the hand-holding, the board has instead issued a FAQ designed to walk trustees through the restructuring process, and re-iterated the guidelines for making the necessary changes to their schemes to allow for a reduction in benefits.

The Irish Association of Pension Funds (IAPF), however, has warned that the criteria the Pensions Board is insisting on are so tight it could force already-weakened pension schemes to wind up rather than restructure. The Pensions Board insists that any restructuring of retirement benefits must be sustainable.

"These schemes can't go off track again in a few years," said a Pensions Board spokesman. "Trustees have to look at the scheme and clearly work out what needs to be done. The promises have to be realistic."

The vast majority of defined-benefit pension schemes – about 90% – are not meeting the regulatory funding standard as a result of the ongoing crisis in financial markets. The situation became so dire last year that social welfare minister Mary Hanafin warned her cabinet colleagues that up to 50% of schemes faced insolvency with a shortfall of €30bn. The revelations led to a relaxing of funding rules allowing schemes more time to correct their balance sheets.

However, a recent IAPF survey reveals that a quarter of defined-benefit schemes have either been wound up or are considering winding up. Most of the schemes that are still operating are implementing less drastic measures – such as capping benefits or pensionable salary – to stay afloat by limiting liabilities to match the amount of money available after the market chaos of the last two years. About half of the wound-up schemes transferred into defined contribution schemes.