Singh will attend the seventh summit of the Group of 20 developed and developing countries (G-20) starting in the Mexican resort town of Los Cabos on Jun 18 and the Rio+20 Summit in Rio De Janeiro.
The G-20 summit is likely to be dominated by the crisis in Europe, which - combined with slowing growth in China and India - poses a threat to the world economy.
The ongoing European sovereign debt crisis has made it difficult or impossible for some countries like Greece and Spain in the euro area to re-finance their government debt without the assistance of third parties.
The Rio Summit, commencing on Jun 20, is being held 20 years after the first Earth Summit, a landmark gathering, in a renewed bid to rally the world behind a common environmental blueprint.
Singh also noted that BRICS (Brazil, Russia, India, China, South Africa) countries have been the new growth poles of the global economy "BRICS leaders have agreed to work with the global community to ensure international policy coordination to maintain macroeconomic stability conducive to healthy recovery of the global economy," he said.
As current Chair of BRICS, India will host an informal meeting of BRICS leaders prior to the commencement of the G-20 Summit to exchange views on the agenda of the Summit.
On the Earth Summit in Rio, the Prime Minister said the cardinal principles of Rio 1992 must not be diluted, particularly the principle of common but differentiated responsibilities as well as equity.
"We have come a long way since the Earth Summit in Rio in 1992. Environmental concerns today occupy the centre-stage of global discourse. Yet, we are far from pursing a truly sustainable path towards development," he said.
The UN Conference on Sustainable Development is a historic opportunity to give meaningful content to paradigm of sustainable development.
At its heart lies the imperative of moving away from a resource intensive development path while ensuring inclusive and balanced development for eradicating the grinding poverty that afflicts millions.
The Rio+20 Conference is likely to debate complex and contentious issues such as green economy and Sustainable Development Goals.
"I will emphasise that we must not dilute the cardinal principles of Rio 1992, particularly the principle of common but differentiated responsibilities as well as equity, which have been at the core of global sustainable development efforts.
"We must acknowledge the continuing differences in levels of development across the world, and the need for provision of financial and technological support to the developing world if we are to work together as a global community to address our most pressing environmental challenges," he said, adding India will work with like-minded countries to forge a consensus in this endeavour.
During his visit, the Prime Minister is expected to hold a separate meeting with Russian President Vladimir Putin, German Chancellor Angela Merkel, French President Francois Hollande, British Prime Minister David Cameron, Canadian Prime Minister Stephen Harper, Chinese Premier Wen Jiabao, Lankan President Mahinda Rajapaksa, Nepalese Prime Minister Baburam Bhattarai and other leaders.