European Union (EU) moves to harmonise pension rules across member states will leave British pensioners "impoverished", Ros Altmann has warned.
Saga's director general said plans to impose ‘unisex' annuity pricing and the ‘draconian' Solvency II funding requirements would be disastrous.
Moves to ban insurers using sex to determine policy prices would, she said, mean much lower pensions for all males purchasing annuities.
Commentators have predicted that if rates are equalised men could see their annuity rates slashed by between 5% and 10%.
She also said Solvency II would push pensions further into deficit as insurers would be forced to hold more low-yielding gilts.
Altmann said: "By trying to foist a set of rules on our pension system - which is very different from most other European countries - the EU could make UK pensioners much poorer than they should be.
"Their search for a 'one-size-fits-all' system does not suit the UK and uniformity across Europe will impoverish British pensioners.
"The government must urgently represent these issues at the highest level before it's too late."
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