Cuts proposed to the benefits paid by the Irish Airlines Superannuation Scheme (IASS) have been criticised by a union for their “very significant adverse effects” on members.

Speaking out after trustees of the IASS reportedly briefed both union and management on their attempts to resolve the €769m deficit within the multi-employer scheme, covering workers employed by the Dublin Airport Authority and Aer Lingus, IMPACT said it and other unions were “very disappointed at the analysis presented”.

IMPACT said: “The trustee reported that the Pensions Board decision to reject elements of the proposals to deal with the funding deficit, which were brokered by the Labour Court and agreed by unions and management at the two companies, would have very significant adverse effects on the pensions of current workers and deferred pensioners.

“The union group will now seek advice from its advisers before deciding how to proceed.”

The trustees of IASS declined to comment on the negotiations.

Attempts to address the deficit were stalled by Ryanair, a major shareholder in rival Aer Lingus, threatening court action if the flag carrier attempted to pay the IASS any additional monies above the agreed contribution rate.

However, following a ruling by the UK’s Competition Commission, Ryanair could be forced to sell down its nearly 30% shareholding, leaving it with only a 5% stake in the company.

A funding proposal discussed, but not submitted, to the Pensions Board earlier this year was questioned by the regulator, as it would have taken the scheme too long to achieve full funding.

Aer Lingus nonetheless hopes to put a €140m plan to launch a standalone defined contribution fund for members affected by the benefit cuts to its shareholders during an extraordinary general meeting later in the year.