* Shanghai stocks lower, blue-chip CSI300 index down
* Gains in Shanghai stocks led by Guangdong Dcenti Auto-Parts Stock Ltd Co and losses by Inly Media Co Ltd
* China's A-shares at a 20.84 percent premium over H-shares
SHANGHAI, May 23 (Reuters) - China stocks fell the most in a month on Wednesday, dragged by a slump in coal miners as Beijing intervened to cool the red-hot coal market.
** The blue-chip CSI300 index fell 1.3 percent to 3,854.58, while the Shanghai Composite Index declined 1.4 percent to 3,168.96 points, their sharpest single-day drop since late April.
** Investors also turned cautious after U.S. President Donald Trump tempered optimism over progress made so far in trade talks between the world's two largest economies.
** Trump said on Tuesday he was not pleased with recent trade talks between the United States and China, souring the improved market sentiment following weekend comments from U.S. Treasury Secretary Steven Mnuchin that trade war is "on hold".
** "The trade tensions between China and the United States have eased somewhat, though it's very unlikely to be the end 'of tension between the two countries'," said Yifan Hu, regional chief investment officer, Greater China, and chief China Economist, UBS Wealth Management.
** Sino-U.S. relationship is entering into a "new normal", and the trade disputes between the two countries would last for several years, Hu added.
** Main sectors fell across the board, led by energy firms. An index tracking major energy firms closed down 4.2 percent, with losses led by coal miners.
** China's largest coal miner, China Shenhua, tumbled 7 percent in its worst day since early 2016, while Yanzhou Coal Mining plummeted the maximum allowed 10 percent.
** China's state planner ordered utilities this week to stop stockpiling thermal coal and told miners to slash prices, two sources familiar with the matter said, the government's first direct intervention to cool coal prices since mid-2016.
** "The rally in coal prices has prompted the government to issue a flurry of measures to bring down prices," said Zhang Min, a coal analyst with Sublime Information.
** Bucking the broad trend, China's auto parts makers surged as Beijing said it will slash import tariffs for automobiles and car parts.
** Around the region, MSCI's Asia ex-Japan stock index was weaker by 0.52 percent, while Japan's Nikkei index closed down 1.18 percent .
** At 07:06 GMT, the yuan was quoted at 6.3817 per U.S. dollar, 0.26 percent weaker than the previous close of 6.3654.
** The largest percentage gainers on the main Shanghai Composite index were Guangdong Dcenti Auto-Parts Stock Ltd Co up 10.02 percent, followed by Guangdong Champion Asia Electronics Co Ltd gaining 10 percent and Changzhou Langbo Seal Polytron Technologies Co Ltd up by 10 percent.
** The largest percentage losers on the Shanghai index were Inly Media Co Ltd down 10.02 percent, followed by Yanzhou Coal Mining Co Ltd losing 9.95 percent and Hunan Salt Industry Co Ltd down by 8.1 percent.
** So far this year, the Shanghai stock index is down 4.2 percent, the CSI300 has fallen 4.4 percent, while China's H-share index listed in Hong Kong is up 3.9 percent. Shanghai stocks have risen 2.82 percent this month.
** As of 07:07 GMT, China's A-shares were trading at a premium of 20.84 percent over the Hong Kong-listed H-shares. (Reporting by Shanghai Newsroom; Editing by Subhranshu Sahu)