Dutch pension funds have warned that they may have to cut their payouts despite the rules being changed to reduce the amount they have to hold in reserve.

The new pension deal included a provision that allowed the funds to lower their level of cover from 100% to 90% during the transition to the new system, which is more dependent on market fluctuations. The funds are required to restore 100% cover by 2026.

Pension funds have been struggling since the last banking crisis to cover their liabilities in full because sustained low interest rates have made it difficult to secure a return on their investments.

Piet Fortuin, chairman of the CNV trade union, said cutting pensions was an unattractive but necessary measure to protect future pensions. ‘We can’t keep tweaking the dials,’ he said. ‘A deal is a deal. We think that most funds will end the year on the right side of the line and any cuts that are needed will be relatively small.’

Piet Rietman, economist with ABN Amro, said half a million people had their pensions invested in funds that could have to announce a cut at the end of this year.

‘It’s not a surprise,’ he said. ‘Under the old pension system actuarial interest is important. And the interest rate is probably going to go down again, partly because of European Central Bank policy.

‘Until 2026, when the new system is due to take effect, we will have to contend with low coverage and therefore cuts.’