The guideline made China the first country where the central government boosts green finance nationwide by building a national system, Chen Yulu, vice-governor of the People's Bank of China, the central bank, said during a policy briefing on Friday.

"The necessity to establish such pilot zones cannot be overestimated as the decision was the first concrete measure to implement the guideline," said Wang Yao, president of the International Institute of Green Finance at the Central University of Finance and Economics.

The pilot zones have already industrialized, or are undergoing industrial upgrading, or are in far-flung and less-developed regions, Wang said. Experience and lessons can be absorbed from different conditions, which can easily adapt to other regions, he added.

"We still lack experience in the new green finance, which demands pilot reforms to find replicable practices in wider regions," the premier told the State Council meeting.

Chen said each of the pilot regions had different conditions. Zhejiang and Guangdong have developed economies and financial sectors, but are eager to upgrade their current development models. How to integrate the financial market with industrial upgrading will be a key for the two provinces, he said.

For example, the city of Huzhou in Zhejiang is already one of the country's five cities which have compiled a "balance sheet" of natural resources. Quzhou city has carried out a pioneering project for green credits, green bonds and industrial funds, Chen said. These advantages will facilitate the establishment of new pilot zones, he added.

In comparison, Guizhou and Jiangxi are less-developed economically, but possess rich resources for green industries. The two provinces are set to boost green finance on their way to a less-polluting model for economic growth, which will focus on modern agriculture, rural drainage systems and energy conservation.

Nevertheless, Xinjiang is an important gateway of the Belt and Road Initiative and will lay more emphasis on fields such as clean energy and high-end manufacturing, including solar power equipment, Chen said.

Lu Zhengwei, chief economist of the Industrial Bank Co Ltd, said each of the five regions has its own conditions while building a green finance system. By carrying out the project, China's green finance will proceed more easily with lessons learnt, he said.