Flows to stocks funds over the past week had helped lift total inflows into equities to $1.0 trillion, BofA said, citing EPFR data. Meanwhile fixed income funds saw the smallest weekly inflows in four weeks at $6.2 billion, while cash funds raked in $7.8 billion.

"10-year U.S. real rates now -4.6% , a level in the past 200 years that has been associated with panics, inflations, wars & depression, and a level today increasingly responsible for froth in crypto, commodities, and U.S. stocks," said Michael Hartnett at BofA.

U.S. equity funds took in $3.3 billion while emerging equities almost matched the intake at $2.7 billion. However, emerging market debt, a lightning rod for higher global yields, suffered the first outflow in four weeks at $900 million, BofA found.

(Reporting by Karin Strohecker, editing by Huw Jones)