World leaders pledged new measures to lead the world toward a more sustainable future on Friday in Rio de Janeiro, Brazil, as they ended a three-day development summit after adopting an outcome document.

In the landmark document, entitled The Future We Want, 191 member states recalled pledges made at the 1992 Rio Earth Summit, vowing to eradicate poverty, advance social equity and ensure a sustainable future for Planet Earth.

Closing the UN Conference on Sustainable Development (Rio+20), the leaders renewed their commitments to global sustainable development and vowed that the world will have to change its growth model based on unsustainable consumption and production.

"It has been a successful conference," UN Secretary-General Ban Ki-moon said at the closing ceremony. "I welcome the adoption of the outcome document."

The text of the 53-page document followed protracted and intense negotiations that the UN chief once called "painfully slow," and was agreed by the member states just one day before the summit opened on Wednesday.

"We, the Heads of State and Government and high-level representatives, ... renew our commitment to sustainable development and to ensuring the promotion of an economically, socially and environmentally sustainable future for our planet and for present and future generations," the text begins.

They reiterated the Rio Principles adopted 20 years ago at the Earth Summit, also held here in Rio de Janeiro, Brazil, in particular the principle of common but differentiated responsibilities, kept in the final text only after developing countries fought vehemently in the negotiations.

Leading industrialized countries, led by the United States, had opposed singling out the particular principle, one of the thorniest issues during the talks.

The document provides "a firm foundation for social, economic and environmental well-being," Ban said with a coarse voice, evidence of numerous speeches and talks at countless events. "It will guide us, all of us, towards a sustainable path."

The summit also formally introduced a new term-- green economy-- to the world, but refrained from offering a clear-cut definition, for there is still no consensus in the international community.

It recognized green economy as one of the important tools available for achieving sustainable development, but stressed there are "different approaches, visions, models and tools available to each country."

Another new step is the decision to seek broader measures of countries' growth to complement data solely drawn on the gross domestic product (GDP), a practice currently used by most countries.

The summit also made headway toward establishing new institutions of sustainable development, including an intergovernmental high-level political forum to eventually replace the UN Commission on Sustainable Development, created by the General Assembly in 1992 to ensure effective follow-up of the Earth Summit.

The UN Environment Program (UNEP) will be strengthened and upgraded to be the global environment authority. Environment is one of the three dimensions of sustainable development, the other two being society and economy.

But it also underlined the role of the UN General Assembly and the UN Economic and Social Council (ECOSOC) in coordinating global sustainability efforts.

A new process to develop the sustainable development goals (SDGs) , one of few issues that member states reached consensus in an early stage, was launched and expected to evolve into an integral part of the post-2015 development framework.

The SDGs "should not divert focus or effort from the achievement of the Millennium Development Goals (MDGs)," a set of eight target that leaders have agreed to achieve by 2015, said the document.

"Today, the MDGs are largely unfinished business," said Hajiya Amina Az-Zubair, a member of the UN High-level Panel of Global Sustainability and former advisor to the president of Nigeria on MDGs.

"It was a minimalist agenda," she told Xinhua on the sidelines of the Rio+20. "The saddest part about it is that we still have not done the minimum."

"We have to finish them to retain the credibility that development matters and that we can set goals that have timelines and targets," she said, calling for "great leadership" and "courage of convictions."

The leaders said they remain "firmly committed to their (MDGs) full and timely

achievement."

But the document contained no specific pledges of funding to support developing countries to achieve sustainability goals.

It did, however, reiterate a call to rich nations to fulfill past commitments, including the one made by many developed countries to achieve the target of 0.7 percent of gross national product (GNP) for official development assistance (ODA) to developing countries by 2015.

"Rio+20 has given us a solid platform to build on," the secretary-general told the leaders. "And it has given us the tools to build with. The work starts now."