China's top economic planner, the National Development and Reform Commission, said it has ordered local authorities to launch probes into illegal increases in food prices.

'Recently, some companies have colluded with each other to conspire in hiking prices, and others have increased hoarding to force up prices,' the NDRC said in a statement.

'The moves severely disturb market prices and exert a negative impact on social stability,' the Commission added.

The probe will focus on manufacturers, wholesalers and retailers of grains, edible vegetable oils, pork, beef and poultry and sectors where these are used as raw materials, it said.

Xie Fuzhan, director of the National Bureau of Statistics earlier said that food prices are unlikely to fall in the near-term, and surging prices will continue to exert pressure on prices overall.

Xie said food prices are highly sensitive to the livestock production cycle and international grain prices.

The Bureau announced earlier that the consumer price index (CPI) rose 3.2 pct year-on-year in the first half and 4.4 pct in June.