* HSI -1.4 pct, H-shares -2.1 pct, CSI300 -0.4 pct
* Ping An slides after 3-mth ban for brokerage unit on IPO fraud
* Commodities-related sectors hurt by weaker physical prices
Hong Kong shares suffered their worst loss in almost a month on Monday as Ping An Insurance fell sharply after regulators slapped a three-month ban on its brokerage unit for helping list a fraudulent Chinese company.
Mainland China markets were also weaker, little moved by data released shortly after midday that showed surprisingly muted factory output growth in April in the world's second-largest economy.
The Hang Seng Index shed 1.4 percent to 22,989.8 points after closing last Friday at its highest since mid-February. This is its worst daily loss since April 15.
The China Enterprises Index of the top Chinese listings in Hong Kong slid 2.1 percent. The CSI300 of the leading Shanghai and Shenzhen listings shed 0.4 percent, while the Shanghai Composite Index slipped 0.2 percent.
"It's definitely a negative and regulators are going to only increase their scrutiny on the brokerage sector, slowing things down even more and adding more uncertainty given the stalled IPO market in the mainland," said Jackson Wong, Tanrich Securities' vice-president for equity sales.
The official China Securities Journal newspaper reported on Monday that the resumption of initial public offerings in China, which some had expected this month or next, will likely be delayed until the third quarter.
Ping An Insurance dived 4.2 percent in Hong Kong in its worst day since July 2012. Its Shanghai listing shed 2.2 percent.
The China Securities Regulatory Commission (CSRC) said on Friday that Ping An Securities, a unit of Ping An Insurance, will face a three-month ban from underwriting after it helped fraudulent firm Wanfu Biotechnology list in 2011.
The unlisted Ping An Securities will also set up a 300 million yuan fund to compensate investors who lost money investing in Wanfu Biotechnology, the Securities Association of China said on its website on Friday.
Ping An Securities had been the most aggressive underwriter targeting small- and medium-sized firms, as it took advantage of a boom in listings on China's Nasdaq-style Chinext board, launched in the southern Chinese city of Shenzhen in 2009.
The Chinese brokerage sector was also among the losers on Monday. Citic Securities , the country's largest-listed brokerage, skidded 4.2 percent in Hong Kong and 1.6 percent in Shanghai.
The growth-sensitive commodities-related sectors were also weak, tracking lower physical prices. Zijin Mining slipped 2.6 percent in Hong Kong and 1 percent in Shanghai as gold prices fell to a near two-week low.
Chinese oil giant CNOOC Ltd slid 2.4 percent in Hong Kong in its worst daily loss since April 15 as Brent futures slipped towards $103 a barrel on Monday.
China's annual industrial output grew 9.3 percent in April, up from a seven-month low of 8.9 percent hit in March but still missing market expectations for a 9.5 percent expansion, data showed on Monday.
Fixed-asset investment, an important driver of China's economy, also missed market forecasts, growing 20.6 percent in the first four months of 2013 compared with the same period a year ago. Economists had expected growth of 21 percent.
Retail sales was the only piece of data that met market expectations, growing 12.8 percent in April from a year ago.