More than 130 world leaders will gather in Rio de Janeiro, Brazil this week, and put their heads together to deliver commitments on making the world a more sustainable place for future generations.

In an exclusive interview with China Daily in New York, Chinese diplomat Sha Zukang, secretary-general for what's billed as Rio+20 and UN undersecretary-general for economic and social affairs, expressed confidence the Brazilian meeting won't be just "another UN conference" but will establish concrete goals.

"The UN is a place where we practically have conferences every day, [but] this is the conference which should have the potential to decide the future of mankind," said Sha.

"Rio+20 must be the place where decisions on the future of the planet are made for the next 10 or 20 years. It cannot be another talk shop. World leaders need to adopt an ambitious and yet practical outcome that equals the magnitude of today's challenges," he added.

The three-day (June 20-22) United Nations Conference on Sustainable Development — its nickname honors the 20th anniversary of the 10992 UN Earth Summit in Rio — will focus on two themes: a green economy, in the context of sustainable development and poverty eradication, and an institutional framework for such development.

Sha said pursuing the first of these goals "can offer win-win solutions. It can be a broad avenue to sustainable development, by opening up new opportunities."

While implementation of environmentally benign technologies has been shown to create jobs and stimulate economic growth while protecting ecosystems, developing countries face transition costs. They also worry that failing to move swiftly toward a greener economy could mean conditions being attached to the aid they receive from developed countries or being hit with trade restrictions.

"These concerns can be alleviated if development partners come forward to offer support in finance and technology, and provide market access for green products for developing countries," Sha said.

"A critical issue is intellectual-property rights, for which I have always stressed the key is affordability. If technologies are not affordable, then all this pledge to international cooperation is just empty talk."

UN member states, during months of negotiations before Rio+20, highlighted a number of challenges to and priorities for reaching the sustainable-development goals, or SDGs, in the conference's dual themes, Sha said. Disaster-risk reduction and resilience, food security and sustainable agriculture, and water access and efficiency are among the priorities world leaders will focus on in Brazil, he predicted.

UN Secretary-General Ban Ki-moon has said Rio+20 is "a once-in-a-generation opportunity" to make concrete progress toward a sustainable economy for the world.

Premier Wen Jiabao, who is scheduled to attend the summit, said on June 7 in Beijing that China supports Rio+20, which "could inject new energy in global sustainable development".

Sha recognizes China's efforts in sustainable development as a leader among emerging economies.

"As a Chinese national, I am very happy that China has established commissions for economic reform and development, which is actually a very strong institution at the national level. They are coordinating all the economic, social and environmental protections," he said.

Rio+20 is also a follow-on to the 1992 Earth Summit, during which countries adopted Agenda 21, a blueprint for rethinking economic growth, promoting social equity and ensuring sustainability.

"Indeed, from climate change to the loss of biodiversity, and from land degradation to depleting fresh water, some of the key challenges that were already apparent in 1992 have unfortunately become even more alarming," the diplomat said.

The conference, he added, "needs to secure strong political commitment at the highest levels of government, and among all stakeholders. It must re-energize the global partnership for sustainable development."

It will also consider establishing a Sustainable Development Council and strengthening the UN Environment Programme by upgrading it to a "specialized agency".

Rio+20 also will strengthen arrangements and mechanisms that integrate sustainable-development goals at international, national and local levels, potentially leading to stronger institutions that ensure access to clean water, sanitation, shelter and energy.

Rio+20 is the biggest UN conference in years, estimated to attract 50,000 people from 190 countries, including heads of State and government along with thousands of participants from the world body and its agencies, civil society and the private sector. Over its three days, the conference will feature over 550 side events organized by the UN itself as well as nongovernmental organizations including environmental advocacy groups.

However, some experts on the environment have voiced skepticism about the event, dismissing it as yet another high-level salon that's unlikely to achieve anything substantial.

Previous UN meetings on global climate change, for instance, ended with a lack of concrete achievements, mostly because of disagreements on language of the final documents among world leaders.

Sha, however, is more optimistic about the Rio gathering, emphasizing that leaders need to adhere to the principle of "common but differentiated responsibilities" — a common phrase at climate-change talks — reconciled with sustainable-development goals.

Countries could determine which goals should be accorded the highest priority in their respective policy-making efforts, based on national circumstances, and then develop specific targets appropriate for them, Sha explained.

"I don't see any conflicts between SDGs and the principle of common but differentiated responsibilities," he said.

The conference, Sha added, will produce a list of measurable commitments. "Major groups, governments and other stakeholders are encouraged to announce at Rio+20 over 1,000 new voluntary commitments for a sustainable future."