The United Nations Conference on Sustainable Development ended on Friday with rights groups and environmentalists calling it a hoax.

The Rio+20 Summit, a 20-year follow-up of the 1992 Earth Summit failed to impress anti-poverty activists and environmentalists who lambasted it as lacking clear ambition to end poverty and to protect the environment.

"Rio will go down as the hoax summit. They came, they talked, but they failed to act," said Barbara Stocking, chief executive, Oxfam, on Friday.

"Governments have embraced globalisation, but failed to govern it. The poorest people on earth are paying the highest price," she added.

Rio+20 held in Rio de Janeiro in Brazil from 20-22 June was attended by the heads of states and ministers of nearly193 nations.

The noticeable absentees at the summit were David Cameron, Barack Obama and Angela Merkel, the heads of rich nations of the world.

The summit ended up with a final document - The Future We Want - that envisages plans to achieve global sustainable development goals such as global environment management, better protection of the oceans, sustainable food security and encourage green economy.

The document was denounced for being soft on the challenges posed by the worsening environment and growing inequality in the midst of the growing population.

The world population is expected to shoot up from seven billion to nine billion in 2050.

"We didn't get the Future We Want in Rio, because we do not have the leaders we need. The leaders of the most powerful countries supported business as usual, shamefully putting private profit before people and the planet," the Guardian quoted Greenpeace International Executive Director Kumi Naidoo ,as saying while calling the summit a failure of epic proportions.

Nonetheless, the leaders expressed hope for achieving the goals. "A more prosperous future is within our reach, a future where all people benefit from sustainable development no matter who they are or where they live," said Hillary Clinton, the US secretary of state.

Take a look at the "Global March" and other forms of protests during the Rio+20:

People look at an image of Guanabara Bay made of recycled trash, part of an installation by Brazilian plastic artist Vik Muniz, during the Rio 20 United Nations Conference on Sustainable Development summit in Rio de Janeiro June 22, 2012.Reuters
Demonstrators hold up an inflatable globe during a march at the People's Summit at Rio 20 for Social and Environmental Justice in Rio de Janeiro June 20, 2012.Reuters
Man holds a kite as Brazilian police officers patrol Flamengo Beach during the Rio 20 United Nations Conference on Sustainable Development summit in Rio de Janeiro.Reuters
Indigenous people dance during the Rio 20 United Nations Conference in Rio de Janeiro.Reuters
Indigenous people arrive at a meeting during the Rio 20 United Nations Conference on Sustainable Development summit in Rio de Janeiro.Reuters
Indigenous people arrive at a meeting in the Rio 20 United Nations Conference on Sustainable Development summit in Rio de Janeiro.Reuters
Demonstrators perform during the march of the People's Summit at Rio 20 for Social and Environmental Justice in Rio de Janeiro.Reuters
Demonstrators perform during the march of the People's Summit at Rio 20 for Social and Environmental Justice in Rio de Janeiro June 20, 2012.Reuters
People protest during a march at the People's Summit at Rio 20 for Social and Environmental Justice in Rio de Janeiro June 20, 2012.Reuters
A demonstrator protests during a march at the People's Summit at Rio 20 for Social and Environmental Justice in Rio de Janeiro June 20, 2012.Reuters
Woman walks past giant fish made with plastic bottles exhibited at Botafogo beach.Reuters