Chinese equities edged down on Monday as market heavyweights remained weak and possibilities of policy tightening turned investors cautious.

The benchmark Shanghai Composite Index on the Shanghai Stock Exchange closed at 3,129.26 points Monday, down 0.51 percent, or 16.09 points.

The Shenzhen Component Index on the Shenzhen Stock Exchange closed at 12,399.2 points Monday, down 155.92 points, or 1.24 percent, from the previous close.

Combined turnover stood at 313.4 billion yuan (45.89 billion U.S. dollars), up from 244.72 billion yuan on the previous trading day.

Gainers outnumbered losers by 485 to 392 in Shanghai and 590 to 305 in Shenzhen.

Property shares led the decline following policies from the central government to cool the property market and check the skyrocketing home prices.

Banks have been required to be more prudent on lending in the property sector, according to Liu Mingkang, chairman of the China Banking Regulatory Commission (CBRC), the country's banking regulator.

The CBRC will boost supervision by checking the borrowers' credit conditions and banning developers from using land as guarantee, he said at the Boao Forum for Asia annual conference over the weekend.

The real estate sector declined 2.45 percent, as China Vanke, the nation's biggest developer by market value, dropped 2.02 percent to 9.2 yuan. Poly Real Estate Co., the second largest, slumped 4.29 percent to 18.76 yuan.

Petroleum heavyweights dropped on declining crude oil prices. PetroChina Co., the country's largest oil producer, went down 0.39 percent to 12.76 yuan. Sinopec, the country's largest oil refiner, declined 2.16 percent to 11.33 yuan per share.

Airliners bucked the trend on rising expectation over yuan appreciation because of their dollar debt. Air China, the nation's flag carrier, jumped 5.54 percent to 14.29 yuan.

The downbeat reflected investors' worries over possible policy tightening, said Lu Hongze, analyst with Shenzhen Securities Information Company.

China reported its first monthly trade deficit in six years over the weekend, and rising imports could be seen as initial signs of overheated economy, he said.

Investors are turning cautious and would wait for the release of the first quarter economic data to make further investment decisions, which is scheduled to be announced this Thursday.

China exports stood at 112.11 billion U.S. dollars in March, up 24.3 percent year on year, while the imports surged 66 percent to 119.35 billion U.S. dollars, resulting in a deficit of 7.24 billion U.S. dollars, the General Administration of Customs (GAC) said Saturday.

China's new yuan-denominated lending in March slumped to 510.7 billion yuan from February's 700.1 billion yuan, the People's Bank of China, the central bank, said here Monday after the market closed.