A transition to a low-carbon "green economy" is crucial for sustainable development, environment ministers from across the world stressed Thursday, concluding the gathering of the Governing Council of the United Nations Environment Programme (UNEP).

The ministers, who have been meeting at the agency's headquarters in Nairobi since Monday, noted that next year's UN Conference on Sustainable Development or "Rio+20" in Brazil will be an opportunity to accelerate a global transition to a low-carbon, resource-efficient green economy.

Green economies would be stronger and geared towards social equity and human well-being, while reducing environmental risks and ecological scarcity, the ministers said, calling on UNEP to support countries keen to "operationalize" the transition.

The ministers, who also constitute the Global Ministerial Environment Forum, expressed concern that the overall efforts of the UN and Member States in respect to the 'environmental pillar' of sustainable development remain weak, underfunded and fractured.

In their summary of discussions, many delegates said countries needed to move beyond pinpointing shortcomings and to focus on a real reform agenda in the run up to Rio+20.

"The efforts to strengthen international environment governance should be about more than rationalization of fragmentation and seeking efficiencies," said the ministers.

"Instead it should be about re-envisioning and even dreaming about what is required institutionally for environment and sustainability, and putting this in place," according to the summary of the meeting, whose chair was Rosa Aguilar Rivero, Minister for Environment, Rural and Marine Affairs of Spain and newly elected President of UNEP's Governing Council.

The summary will form a key input of ministers responsible for the environment into the year-long preparations for the Rio+20 conference, which is scheduled for early June 2012.