China's top securities watchdog slowed down on approving A-share initial public offerings (IPOs), in a bid to quell liquidity drain and market volatility.

The China Securities Regulatory Commission (CSRC) green-lit only four IPOs last week, after cutting down approved cases from 10 to 7 in the previous week.

The four companies will raise no more than 1.5 billion yuan ($220 million), plummeting from the 2.3 billion yuan approved a week earlier, according to statements from the CSRC. Dining chain Guangzhou Restaurant Co and chemical material manufacturer Tangshan Sunfar Silicon Industry Co will list on the Shanghai main board.

Despite the slowdown on approval, the A-share market is not expected to see an overall hiatus on new share issuance, reported China Business News citing a source close to the matter.

The IPO curb reflects the regulator's determination to stabilize market expectations in the midst of potential risks such as share pledge, Wang Sheng, chief strategic analyst with Shenwan & Hongyuan Securities, told the newspaper.

The move comes as lock-up shares worth about 50.75 billion yuan are becoming eligible for trading this week.

According to A-share rules, major shareholders must wait one to two years before they are permitted to sell their shares.

The CSRC has recently added restrictive measures on stock-selling by big shareholders. Shares transferred through block trades should be below 2 percent of a company's total in any 90 days, under the new rule.

The CSRC has approved 199 IPOs to raise no more than 100.4 billion yuan so far this year.

Tan Xinyu contributed to this story.