Chinese bourses have set daily restrictions on net share sales by hedge funds and large retail investors, four sources said on Friday, as Beijing steps up support for its stock markets in an intensifying trade war with the United States. Two investor sources said a soft limit on daily net sales by individual hedge funds and big retail investors - implemented through verbal warnings from brokerages - had been set at 50 million yuan ($6.83 million). Failure to comply risked a suspension of trading accounts by the stock exchanges, which have issued the directive, two brokerage sources said.