Zhang also said the regulator supported long-term investors, including pension funds, insurers and Qualified Foreign Institutional Investors (QFII) to enter the stock market to stabilise prices. The QFII scheme is one of the main channels of foreign investment in the country's capital market.
China's main stock indexes have fallen nearly 30 percent since mid-June despite series of government measures to stem the sell-off.
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Zhang also said China Securities Finance Corp, China's official margin lender for brokerages, would boost its capital base to 100 billion yuan ($16 billion) from 24 billion yuan and would further raise money from various channels to expand business and stabilise markets.
Many analysts suggest high levels of margin borrowing have exacerbated the falls as investors have been forced to sell assets to meet margin collateral requirements.