Image caption The current "brown" economy is carbon and resource intensive and is not sustainable, the study says

Investing $1.3 trillion (£800bn) each year in green sectors would deliver long-term stability in the global economy, a UN report has suggested.

Spending about 2% of global GDP in 10 key areas would kick-start a "low carbon, resource efficient green economy", the authors observed.

They also recommended following policies that decoupled economic growth from intensive consumption.

The findings have been published at a meeting attended by 100 ministers.

"Governments have a central role in changing laws and policies, and in investing public money in public wealth to make the transition possible," said Pavan Sukhdev, head of the UN Environment Programme's (Unep) Green Economy Initiative.

"Misallocation of capital is at the centre of the world's current dilemmas and there are fast actions that can be taken, starting literally today," he added.

"From phasing down and phasing out the $600bn global fossil fuel subsidies, to re-directing more than $20bn subsidies perversely rewarding those in unsustainable fisheries."

Unep defined a "green economy" as one that resulted in "improved human well-being and social equity, while significantly reducing environmental risks and ecological scarcities".

When it came to investing 2% of GDP in greening the global economy, the authors recommended a number of investments, including:

$108bn greening agriculture, such as encouraging and supporting smallholder farms

$134bn on the building sector, including improving energy efficiency

$110bn improving fisheries, including reducing the capacity of the world's fishing fleet

$15bn on forestry, with "important knock-on benefits for combating climate change"

Almost of $110bn on both water and waste, including sanitation and recycling

The report, produced by experts from developed and developing nations, suggests that the green economy model would deliver higher annual growth rates within 5-10 years than a business-as-usual scenario.

In order to unlock the level of investment required, it added that it was necessary to reform existing national and international policies.

"The green economy - as documented and illustrated in the report - offers a focused and pragmatic assessment of how countries, communities and corporations have begun to make a transition towards a more sustainable pattern of consumption and production," said Unep executive director Achim Steiner.

"With 2.5bn people living on less than $2-a-day and with more than two billion people being added to the global population by 2050, it is clear that we must continue to develop and grow our economies.

"But this development cannot come at the expense of the very life support systems on land, in the oceans or in the atmosphere that sustain our economies, and thus, the lives of each and everyone of us."

The findings are being published at the 26th session of Unep's Governing Council/Global Ministerial Environmental Forum, which is being held in Nairobi, Kenya, until 24 February.