Businesses running final-salary pensions are being "clouted" by the government's quantitative easing (QE) programme, says the National Association of Pension Funds (NAPF).
The NAPF claimed QE has knocked £90bn off the value of final-salary schemes as it has made government bonds, in which pension funds are big investors, more expensive to buy.
This, it said, has served to increase the schemes' deficits.
Joanne Segars, chief executive of the NAPF, said: "Businesses running final-salary pensions are being clouted by QE.
"Deficits that were already big now look even bigger because of its artificial distortions.
"Firms are legally obliged to fill the deficits, and that diverts money away from jobs and investment, and will lead to further closures of final salary pensions in the private sector," she warned.
The NAPF said QE has also made it more expensive for people retiring with personal pension pots to convert this money into annuities - an annual income for life.
That is because annuities are funded by insurance firms investing the pensioners' money mainly in government bonds.
"Falling annuity rates mean the average person with a pension pot of £26,000 retiring now would get 22% less income than if they had annuitised four years ago. This is a loss of £440 a year," the NAPF said.
The association said it wanted both the Bank of England and the Pensions Regulator to make it clear that rising deficits were artificial.
The NAPF said the regulator should let schemes calculate their liabilities by using a more generous return, in line with the return on corporate bonds.
Last month, the Bank agreed to extend its programme of QE by a further £50bn, to an eventual £325bn.
The first round of QE, which started in 2009, is estimated by the NAPF to have increased the cost of funding the UK's final-salary pension schemes by about £180bn.
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