Negative interest rates risk hitting consumer spending and undermining the economic growth they are intended to encourage, the head of the world's largest asset management group has warned.
Larry Fink, chief executive of BlackRock, said that not enough attention was being given to the effect of negative rates on saving habits in a downbeat annual letter to his shareholders.
His intervention came as the International Monetary Fund added fuel to the debate on what effect negative interest rates were having on the global economy by warning that there were "limits on how far and for how long negative policy rates can go".
The fund said the introduction of negative policy rates by central banks such as the Bank of Japan had been broadly positive so far, but highlighted the danger of reaching a tipping point where people would start to hoard cash.
The Bank of Japan, the European Central Bank and four other central banks around the world have introduced overnight negative interest rates in an effort to bolster growth and raise inflation expectations. The monetary policy experiment is designed to encourage banks to lend, but its introduction has been accompanied by doubts over its effectiveness, concern about its effects on bank profitability and by widespread volatility in financial markets.