Governments around the world have been urged to outline their pledges to cut greenhous gas emissions by midnight Sunday. So who has responded and how much have they pledged?
Nations have been reaffirming their plans in support of last month's Climate Summit in Copenhagen.
But critics say without a binding agreement, the pledges fall short of actually making a difference.
Copenhagen is already being remembered as the conference where a binding agreement wasn't reached.
Instead, the Summit concluded with a so called Copenhagen Accord, a pledge to limit global warming to below 2 degrees Celsius.
News that makes sense
Your trusted source for staying up-to-date with the world around you. Get free daily news updates and analysis, straight to your inbox.
It's the non-binding document crafted by a small group of countries, responsible for roughly 80 per cent of world carbon emissions.
Overnight was the deadline for their signatures.
In addressing African Nations, UN Chief Ban Ki Moon told delegates their countries were among the least responsible for greenhouse gases, yet the most susceptible to climate change.
"The Copenhagen accord represents an important step forward. I welcome those African countries who have already become associated with the accord and I urge others to do the same as soon as possible," Mr Ban said.
So exactly which countries have pledged cuts and by how much? Some of the figures are not new and have been revealed before, but it's been seen as a reaffirmation of intent.
Two of the world's biggest polluters are promising a reduction in carbon intensity, which isn't the same as reducing carbon dioxide.
It simply means emissions will continue to rise in the long term, but at a slower pace as the country develops and advances in productivity.
So who has responded and how much have they pledged?
China is promising to slash its carbon intensity by up to 45 per cent, while India is proposing up to 25 per cent.
As for actually cutting emissions, Brazil is pledging up to 39 per cent, Japan, 25 per cent, 20 per cent for the EU 17 per cent from the US, while Australia is trailing significantly behind, with a promise of 5 per cent.
There are no sanctions in place if countries break their promise because of this, and critics say the accord falls shorts on what is needed to make a difference.
But others believe it's an indicator of prospects for a legally binding deal later in the year.
The next round of negotiations is scheduled in December in Cancun, Mexico, and at the weekend, the country's President said a lack of trust and the economic problems need to be overcome first.
"And the way to do so is again to establish an economic system in which we can fix the environmental challenges and at the same time we can provide economic opportunities for the poorest people in the world. Is that possible? Yes!," Mexican President Felipe Calderon said.
The Accord may not be legally binding and may fall short of the targets pledged, but it shows the intent that countries want to cut or curb their greenhouse gas emissions.
