Seventy-five countries accounting for more than 80 percent of greenhouse gases from energy use have filed pledges to cut or limit carbon emissions by 2020, the UN climate convention said Wednesday.

The promises, made under the Copenhagen Accord, are only a step towards wider action to tackle global warming, the UN Framework Convention on Climate Change (UNFCCC) said in its official report on December's world climate summit.

A total of 111 countries plus the European Union (EU) "have indicated their support for the Accord," the UNFCCC said.

Cobbled together in the summit's crisis-ridden final hours, the Copenhagen Accord sets the goal of limiting warming to two degrees Celsius (3.6 Fahrenheit), gathering rich and poor countries in action against carbon pollution that causes the problem.

It also promises 30 billion dollars for climate-vulnerable poor countries in the three years to 2012, and up to 100 billion dollars annually by 2020.

Supporters point out it is the first accord to include advanced and emerging economies in specified emissions curbs.

Critics retort that it has no deadline for reaching the warming target, has no roadmap for reaching it and its pledges are only voluntary.

The UNFCCC's report on Wednesday confirms that major emitters, including China, India and Brazil, have given the Accord their political blessing.

After more than two months of foot-dragging, the emerging giants separately aligned themselves with the document in early March.

UNFCCC Executive Secretary Yvo de Boer said the promises were significant but not the final answer.

"It is clear that while the pledges on the table are an important step towards the objective of limiting growth of emissions, they will not in themselves suffice to limit warming to below 2 C (3.6 F)," he said.

"The climate conference at the end of this year in Mexico therefore needs to put in place effective cooperative mechanisms capable of bringing about significant acceleration of national, regional and international action both to limit the growth of emissions and to prepare for the inevitable impacts of climate change."

The December 7-19 confab drew attendance from 120 heads of state or government, the highest for any climate meeting.

It was initially touted as the culmination of a two-year negotiation process towards a global pact from tackling climate change beyond 2012, when the Kyoto Protocol's current provisions expire.

But delaying tactics and textual warfare, reflecting entrenched national interests and concern over the cost of switching out of carbon-intensive fuels, drove the summit to near-collapse.

In the end, heads of around two dozen countries, led by the major emitters, huddled together to produce the Accord.

The first official talks under the 194-nation UNFCCC will take place in Bonn, western Germany, from April 9-11.

Negotiators will be tasked with breathing life into the Copenhagen deal and seeing how it integrates with the labyrinthine two-track UNFCCC process.

Greenhouse gases are mainly carbon dioxide from burning coal, oil and gas as well as methane from forest loss and agriculture.

They are blamed for trapping the Sun's heat in the atmosphere, instead of letting it radiate safely back into space.

The warming is changing the delicate ballet of Earth's climate system -- and by century's end, many millions could be afflicted by drought, floods, rising seas and severe storms, experts fear.

To achieve the 2C (3.6 F) goal by 2100, rich countries would have to cut their emissions by 25-40 percent by 2020 over 1990 levels, while developing countries would have to brake their emissions by 15-30 percent below forecast trends.