BEIJING -- A senior official on Wednesday vowed to prevent rebounds in property prices in the second half of the year.

"We will stabilize control measures to curb speculation and increase housing supplies, especially small- and mid-sized housing", said Zhang Ping, head of the National Development and Reform Commission, in a report delivered at an ongoing bimonthly session of the national legislature.

The country's tightened property controls have seen some results, as average home prices in 58 out of a statistical pool of 70 cities dropped in July, Zhang said.

Zhang also spoke about the results of a government-designed welfare housing project designed to help low-income groups. Construction on 5.8 million low-income housing units, or 77 percent of the government's 2012 target, had started by the end of July, he said.

Authorities have strengthened supervision over the construction, distribution and management of such units, Zhang added.

Minister of Finance Xie Xuren also addressed property issues in a separate report on Wednesday, stating that the central government invested 195.3 billion yuan ($30.8 billion) in low-income housing projects from January to July.

Intensive home price controls contributed to a drop in government income from the transfer of rights for state-owned land in the first seven months, which was 27.1 percent lower year-on-year, said Xie.

Xie pledged to promote property tax reforms on a trial basis and strictly implement differentiated taxation policies for property transactions.