China's stock market watchdog has approved the initial public offerings of 20 firms, it said late on Monday, around double the number it approved on average last year.

The move is seen aimed at tempering the country's red-hot stock market, which gained more than 40 percent in the fourth quarter last year.

"Apparently, regulators are increasing new share supplies amid the recent market bull run," the semi-official China Business News said in a report on Tuesday.

"The market expects the number of IPOs hitting the market will continue to increase."

Last year, the China Securities Regulatory Commission (CSRC) approved about 10 IPOs per month, with the go-aheads given near the end of each month.

All 20 companies approved on Monday were relatively small companies, with 10 aiming to list on the Shanghai Stock Exchange and the rest on the Shenzhen Stock Exchange.

Of the 20, 17 launched their IPOs on Tuesday including Fujian Torch Electron Technology Co, Shanghai M&G Stationery Inc and Western Region Gold Co.

The CSI300 index of top Chinese companies rose 44 percent during the fourth quarter in what some analysts have dubbed a "crazed bull run."