SHANGHAI, Aug 9 (Reuters) - Red-hot shares of Chinese building materials companies dipped on Wednesday as investors took profits on a months-long rally, weighing on broader benchmark indexes.

The CSI300 index was 0.1 percent higher at 3,736.27 points by midday, while the Shanghai Composite Index lost 0.2 percent to 3,275.01.

A gauge of materials shares slipped 0.3 percent as some investors cashed in after a near 30 percent jump since the beginning of June, which is being fueled by a year-long construction boom and higher prices for products from cement and glass to steel.

Hesteel Co Ltd fell 2.3 percent.

The sector slid despite data showing China's producer price index grew at a steady pace in July, boding well for industrial output and profits at the start of the third quarter.

Joe Qiao, an analyst at Xiangcai Securities in Shanghai, noted that the producer price inflation reading of 5.5 percent had been widely expected. It has held at the level for three straight months, though economists maintain it will start to cool by year-end.

Beijing on Wednesday summoned steel executives and regulators to discuss steel prices following the recent surge.

Investors in alcohol shares were in higher spirits, boosting consumer staples and supporting the broader indexes. Baijiu maker Luzhou Laojiao Co rose 3.7 percent, and Wuliangye Yibin Co rose 3.3 percent.

In Hong Kong, shares retreated in line with regional losses as escalating tensions between the United States and North Korea prompted investors to book profits on recent gains.

Pyongyang said on Wednesday it was "carefully examining" a plan to strike Guam, home to a U.S. military base that includes a submarine squadron, an airbase and a Coast Guard group.

"Sentiment is a bit short because of the U.S. and North Korea issue, the political uncertainty," said Andy Lam, investment strategist at Harris Fraser Group in Hong Kong.

"It's just a pause for the market, especially as you notice in the last two to three days, the Hang Seng index was driven by Tencent."

The Hang Seng index dropped 0.8 percent to 27,629.68.

Tencent Holdings Ltd fell 0.5 percent, falling from the previous session's record-high close of HK$328.60.

The Hong Kong China Enterprises Index lost 1.5 percent to 10,918.35.

The index measuring price differences between dual-listed companies in Shanghai and Hong Kong stood at 127.62.

A value above 100 indicates Shanghai shares are pricing at a premium to shares in the same company trading in Hong Kong, and vice versa.

(Reporting by Andrew Galbraith; Editing by Kim Coghill)