Chengdu's high-tech zone has grown quickly both by attracting foreign firms and by supporting local small and medium-sized enterprises (SMEs), a zone official told the Global Times in an exclusive interview Thursday.

Established in 1991 as one of China's first high-tech zones, the Chengdu High-Tech Industrial Development Zone has become the fourth best in the nation, Tang Jiqiang, director of the zone's Strategic Development Planning Bureau, told the Global Times Thursday, citing a Ministry of Science and Technology ranking of comprehensive competitiveness including sustainability, globalization, and industrialization capacity.

China has named more than 100 high-tech zones nationwide, and Tang said Chengdu is outranked only by Beijing's Zhongguancun, Shanghai's Zhangjiang and a third in Shenzhen.

The Chengdu zone has grown partly due to its good location, convenient transportation, and openness, Tang said.

Chengdu contains 10 consulates from nations including the US and Germany, but its biggest advantages are its modern, globalized service system and large number of professionals, he said.

By June, more than 100 Fortune 500 firms and leading international businesses had opened offices in the Chengdu high-tech zone, including Intel, Hewlett-Packard and some of the best software companies, making it an international base of electronic information, software and optoelectronics, Tang said.

However, he noted that it was private local firms, especially small and medium-sized technical firms, that contributed the most.

The zone promotes business development using the idea that businesses grow in stages, with different financing needs at each stage, Tang said. It therefore created a financing model that offers different types of financial support at different development stages, he said.

For enterprises just starting up, the zone offers up to 100,000 yuan in startup funds and a rent-free office. It provides bank loan guarantees and helps find venture capital (VC) investment for growing and expanding enterprises. When the enterprises have matured, they can get government support for a stock listing, Tang explained.

The government not only brings in VC, but also established its own fund to support more SMEs, Tang said. The fund has invested 80 million yuan in firms within the zone this year.

Such government investments can also earn big returns. "We have invested billions of yuan to support companies, and in return, they have brought us more than 10 billion yuan in revenue since the zone was founded," Tang said.

Occupying only 0.02 percent of the area of Sichuan Province, the Chengdu high-tech zone produced one-tenth of Chengdu's GDP and one-tenth of Sichuan's financial revenue in 2011.

However, the 130-square-kilometer zone, much smaller in size than most of its peers, offers limited space for a fast-growing economy, Tang said.

Chengdu has grown quickly because of its mild climate and strong industrial foundations, Liu Weixin, a researcher with the Chinese Academy of Social Sciences, told the Global Times Thursday.

However, recent development, especially in the fast-growing manufacturing sector, has used more and more farmland, Liu said, suggesting that it should develop service, high-tech and finance industries within the city while moving manufacturing to surrounding areas.