Ant Group’s money market fund has shrunk to a more than four-year low as users shifted their cash in the face of China’s crackdown on Jack Ma’s payments group.

Funds invested in Ant’s flagship Yu’e Bao fund fell 18 per cent in the first three months of the year to Rmb972bn ($150bn) as the group pushed users to switch to other providers’ funds, according to data released on Thursday by its Tianhong Asset Management subsidiary. The money-market fund, once the world’s largest, acts as the main repository for leftover cash stored by hundreds of millions of users of Ant’s Alipay payments app.

The fall came as Chinese authorities have piled pressure on Ma’s internet empire since abruptly halting Ant’s $37bn initial public offering, which would have been the world’s largest, in November. Ma has barely been seen in public since the listing was scuppered and regulators fined Alibaba, Ant’s ecommerce sister group, a record $2.8bn for anti-competitive behaviour this month.