Traditionally, the integration concept includes the cities of Shanghai, Nanjing, Suzhou, Yangzhou, Zhenjiang, Taizhou, Wuxi, Changzhou, Nantong, Hangzhou, Ningbo, Huzhou, Jiaxing, Zhoushan, Shaoxing and Taizhou. The two new documents would extend it to include less-developed areas in Jiangsu and Zhejiang.

Tu Qiyu, a researcher from Shanghai Academy of Social Sciences, said Monday that the expanded integration would unify administrative systems in Jiangsu and Zhejiang and make cooperation easier within the zone.

"Instead of the current 'one province, two systems' policy in Jiangsu and Zhejiang, the change will broaden cooperation in more respects and make for a more harmonious development in the whole area," Tu said.

The seminar, opened on December 1, highlighted regional environmental protection and sustainable economic development, unification of the delta's market, sharing 2010 Shanghai Expo opportunities and expanding the expo's effects.

To remove administrative barriers to further integration within the zone, industry and commerce administrators in Shanghai and its two neighbors also signed a joint memorandum of understanding on unifying market access for businesses in the region.