Vice-Minister of Science and Technology Wang Weizhong talks about the country's transition to green economy on Wednesday at a side event of the Rio+20, the United Nations Conference on Sustainable Development. Larry Lee / China Daily

A senior Chinese official warned of significant hurdles his country faces in trying to move to cleaner forms of energy and called for global cooperation in the effort.

"As a developing country with a population of 1.3 billion, of which 122 million people live below the poverty line, China has to tackle severe challenges in its transition to a green economy," Wang Weizhong, vice-minister of science and technology, said Wednesday at a side event coinciding with the official start of the United Nations Conference on Sustainable Development, known as Rio+20.

Wang said a relatively weak technology base and limited capability in research and development constrain China's green development, along with a lack of core technologies for transforming traditional industries and huge socioeconomic imbalances among different Chinese regions and between urban and rural areas.

"Protecting the environment, eliminating poverty and stimulating growth in ecologically vulnerable areas of the western region are particularly formidable," said Wang. He headed China's administrative office for Agenda 21 from 1998 to 2006. Agenda 21 was the action plan for sustainable development adopted at the first UN "Earth Summit" in Rio de Janeiro in 1992.

The vice-minister pointed out that with a low income per capita, average consumers in China have limited spending power to buy environmentally friendly goods, which typically cost more. "This is an obstacle we can't ignore in promoting green consumption," Wang said.

But he said China will stay on the path of green development despite these difficulties, citing the binding targets set in the country's 12th Five-Year Plan (2011-2015) for environmental protection, energy conservation and emission reduction.

During the five years, China's energy consumption per unit of gross domestic product is expected to be reduced by 16 percent, while the volume of emissions of major pollutants is to be cut dramatically.

Wang said the Chinese government has decided to slow economic growth to 7 percent annually in order to promote a green transformation. However, he expressed hope that the world at large will build up collaboration toward that goal.

"Developed countries should encourage technology transfer in accordance with their commitments, and strengthen technical assistance and R&D cooperation for developing countries, so as to help the latter's green transition," said Wang, who is a water resources expert by profession.

Veerle Vandeweerd, director of the UN Development Programme's Environment and Energy Group, praised China's efforts in promoting sustainable development and a green economy.

Like many, she described China's 12th Five-Year Plan as the "Green Plan" and "one of the most ambitious to date in terms of environment, energy and climate change and focusing on the quality of growth".

The UNDP will continue to work closely with China on sustainable development, said Vandeweerd. "In China today, we see that political will is strong and rising. We need to help the world to transit to a new society, a new economy, a world more in harmony with nature. China is leading the way and UNDP is there to help," the Belgian scientist and veteran UN environmental official said.

Her agency has worked with China in a range of areas, including rapid urbanization, technological innovation and South-South cooperation, which builds on Chinese success in lifting more than 600 million people out of poverty over the past 30 years.

"We are charting the way to a post-consumption society," Vandeweerd said. "Charting this way will not be easy."

China, with one-fifth of the world's population, understands this all too well, she said. "A global unsustainable world means an unsustainable China; an unsustainable China means a global unsustainable world. So simple the mutual dependency has become."

chenweihua@chinadaily.com.cn