The UN\'s climate chief urged negotiators gathering on Monday for new talks to heed a double dose of "bad news" that global warming could bust a threshold widely considered safe.

Greenpeace activists burn a symbol of carbon dioxide as they demonstrate in 2008 in Berlin.(AFP/DDP/File/Theo Heimann)

Christiana Figueres, executive secretary of the UN Framework Convention on Climate Change (UNFCCC), urged nations at the 12-day talks in Bonn to uphold their pledge to peg warming to 2.0 degrees Celsius (3.6 degrees Fahrenheit).

"Now, more than ever, it is critical that all efforts are mobilised towards living up to this commitment," she said in a webcast press conference.

Figueres pointed to "bad news" in the form of carbon emissions data released by the International Energy Agency (IEA) and the US National Oceanic and Atmospheric Administration (NOAA).

The Paris-based IEA said last month that carbon from energy use reached a record high in 2010 while NOAA said atmospheric levels of carbon dioxide (CO2) in May had scaled a new peak.

The Bonn talks are meant to lay the groundwork for the next round of high-level negotiations in December in Durban, South Africa.

Some wealthy nations led by the United States favour restricting the scope of the Durban round to consolidating progress made in Cancun, Mexico, last December.

These include the creation of a "green fund" for developing countries that could reach 100 billion dollars a year, a system for monitoring national schemes to reduce emissions, and programmes to boost clean technologies and help poor nations cope with climate change.

"If we take these steps and start to build the new institutions needed for a pragmatic international regime, COP 17 in Durban will be a solid success," said Jonathan Pershing, the top US negotiator in Bonn.

Developing nations, led by China and other major emerging economies, have embraced these goals, but major disagreements remain on how they should take shape.

Another big area of discord is over the future of the UNFCCC\'s Kyoto Protocol, the sole treaty that sets down legally-binding emissions targets.

These requirements only apply to advanced economies, except the United States, which refuses to ratify Kyoto.

The "G77 and China" group -- a bloc of 131 developing countries -- reiterated Monday its demand for Kyoto pledges to be renewed when the present commitment period ends at the end of 2012.

This would be "one of the key outcomes" in Durban, the group said in a press release. "Its continuity demands a strong political decision from all parties."

Russia, Japan and Canada, however, have said they will not sign up for a new round of cuts unless rising giants such as China, India and Brazil accept constraints as well.

The European Union (EU) on Monday backed a second roster of pledges but warned this position should not be taken for granted.

"There is the impression that the EU will easily move into a second commitment period, that it is a foregone conclusion. That is not the case," said Artur Runge-Metzger, the chief negotiator.

The EU will renew Kyoto vows "only if there is also agreement on the other side towards an agreement that covers all those major economies at the same time," he said. "It cannot stand alone."

European nations, he pointed out, only account for 11 or 12 percent percent of global greenhouse gas emissions.

"We would not see that as success in Durban to say... \'we don\'t have anything else for the other 88 or 89 percent\'."

Figueres said that there was some good news despite scientific gloom.

"Quite a few countries, including the biggest economies, are clearly building new policies that promote low carbon goals," she told journalists, citing China and Britain in particular.

Private capital was also flowing into low-carbon technologies, she said, noting that the UN climate scientists concluded recently that, by mid-century, up to 80 percent of the world\'s energy needs could come from renewable sources.