Blind and excessive land exploitation in China's urbanization may partially contribute to the sharp decrease of the country's arable land and pose a threat to food security, a senior official has warned.

"We should not excessively turn farmland into urban areas. Grain security should be given priority," Yang Weimin, secretary-general of the National Development and Reform Commission, the top economic planning body, said at a forum about urbanization strategy and planning over the weekend.

Yang said the country has approved more than 1,500 national- and provincial-level industrial development zones, the area of which account for nearly 1 million hectares.

"But not all places need to massively boost industrialization and urbanization. For example, we should leave major agricultural and ecological areas as they are and limit their urbanization," he said.

Newly built urban areas in China had grown by 50 percent since 2000, while the urban population increase by only 26 percent during the same period, Yang said, which means the country's speed in urbanizing land almost doubles the rate for the urbanization of the population.

Chen Xiwen, director of the office for the Communist Party of China Central Committee's Leading Group on Rural Work, said last week that China's arable land had declined by 8.3 million hectares in the past 12 years partly as a result of the country's urbanization.

However, Chen said the pursuit of high urbanization was unnecessary and that ensuring balanced urbanization and rural development, and the development of both big and small cities, was more important.