Land prices and transaction volumes both declined on a monthly basis in Chinese cities amid a sluggish market last month, a research institute said Sunday.

The China Index Academy (CIA), a Beijing-based company that studies China's property market, said in a report that the average floor price for residential land in 133 Chinese cities currently being monitored by the institution declined 9 percent to 1,619 yuan ($253) per square meter in August.

Meanwhile, transaction volumes for residential land in the cities continued to drop last month to 20.18 million square meters, down 17 percent month-on-month and down 14 percent from a year earlier, said the CIA.

The land market has become increasingly vulnerable since the government announced in August that it would extend restrictions for residents buying their second or third homes to the country's second- and third-tier cities, according to the CIA. These restrictions previously existed only in 43 of the country's largest cities.

The CIA expects land prices to remain steady in the near future, according to the report.

Earlier CIA data showed that 44 major Chinese cities saw prices for new homes fall in August as the result of tightening measures that were put in place to cool down China's property market.