"We will strive to make some decisions in the Rio+20 which serve the interests of the nations," President Ahmadinejad said before leaving Tehran for a tour of Latin America which will take him first to Bolivia and then to Brazil and Venezuela.

"We believe that progress should be based on respect for human beings as well as the divine and humane values and grandeur," he added.

He described one-sided progress which destroys the environment as merely beneficial to the interests of capitalism and a contributor to increased poverty in the world, and said, "Continuing such an approach is not correct at all and those whose population is about 5% of the Earth's population and have the lion share in destroying the environment should correct their behavior."

Delegates from around the world will descend on Rio de Janeiro this week for 'Rio+20' summit, a major United Nations meeting on the environment. The event will commemorate the 20th anniversary of the first 'Earth Summit'.

To a large extent, the conference is split into two parts: negotiations around the formal text, which will become the official outcome document for the summit, and the informal sessions.

In the former, negotiators are wrangling over the words that will hopefully culminate in a meaningful global agreement on sustainability.

In the informal sessions, groups and individuals are meeting to discuss the issues of the day and will hopefully come up with ideas that will help us make headway on the big environmental challenges, like climate change, water scarcity, and deforestation, among many others.