BEIJING (Reuters) - The northern city of Tianjin has become the latest Chinese city to restrict property purchases, the city government said late on Friday (Sept 30), as second- and third-tier cities across the country try to cool rising home prices.

In a statement posted on its website, the city said it would stop people who do not have the "hukou" residence permit for Tianjin from buying a second property in the downtown area.

Down payments for non-residents in downtown locations will also have to be no less than 40 per cent of the purchase price, it added, without saying what it was before.

Tianjin is the newest second-tier city to introduce measures to restrict home purchases in response to surging home prices. Nanjing, Hefei, Suzhou, Xiamen and Hangzhou have introduced similar measures.

The average new home price in 70 major cities climbed an annual 9.2 per cent in August, up from 7.9 per cent in July, according to data from China's National Bureau of Statistics.