Global leaders have wrapped up the UN development summit, the Rio+20 summit in Brazil. Its secretary general, Sha Zu-kang, told a news conference that it had made significant progress.

Sha Zukang, Secretary General, Rio+20 Summit, said, "So now, let me update you on the numbers. The total figure is now 692 registered commitments. Ladies and gentleman, this brings the estimated total value of commitments to 513 billion US dollars. This is a major achievement."

Among all the achievements, the signing of an agreement covering various fields should be the greatest one.

Despite the fact that the agreement ranges from energy to food security to oceans was signed, some signatories describe the agreement as lacking commitment, specifics and measurable targets.

The agreement calls for the launch of a process to agree sustainable development goals. Compared with the original Earth Summit in 1992, which led to historic decisions on bio-diversity and greenhouse gas emissions, organisers say this week’s conference is only the beginning of a new goal-setting process for global development.