Seeking to control global warming, nearly 200 countries agreed Saturday to extend the Kyoto Protocol, a treaty that limits the greenhouse gas output of some rich countries, but will only cover about 15 percent of global emissions.

The extension was adopted by a U.N. climate conference after hard-fought sessions and despite objections from Russia. The package of decisions also included vague promises of financing to help poor countries cope with climate change, and an affirmation of a previous decision to adopt a new global climate pact by 2015.

Though expectations were low for the two-week conference in Doha, many developing countries rejected the deal as insufficient to put the world on track to fight the rising temperatures that are shifting weather patterns, melting glaciers and raising sea levels. Some Pacific island nations see this as a threat to their existence.

``This is not where we wanted to be at the end of the meeting, I assure you,'' said Nauru Foreign Minister Kieren Keke, who leads an alliance of small island states. ``It certainly isn't where we need to be in order to prevent islands from going under and other unimaginable impacts.''

The two-decade-old U.N. climate talks have so-far failed in their goal of reducing the carbon dioxide and other greenhouse gas emissions that a vast majority of scientists says are warming the planet.

The 1997 Kyoto Protocol, which controls the emissions of rich countries, is considered the main achievement of the negotiations, even though the U.S. rejected it because it didn't impose any binding commitments on China and other emerging economies.

Kyoto was due to expire this year, so failing to agree on an extension would have been a major setback for the talks. Despite objections from Russia, which opposed rules limiting its use of carbon credits, the accord was extended through 2020 to fill the gap until a wider global treaty is expected to take effect.

However, the second phase only covers about 15 percent of global emissions after Canada, Japan, New Zealand and Russia opted out.

The decisions in Doha mean that in future years, the talks can focus on the new treaty, which is supposed to apply to both rich and poor countries. It is expected to be adopted in 2015 and take effect five years later, but the details haven't been worked out yet.

U.S. climate envoy Todd Stern highlighted one of the main challenges going forward when he said the U.S. couldn't accept a provision in the Doha deal that said the talks should be ``guided'' by principles laid down in the U.N.'s framework convention for climate change.

That could be interpreted as a reference to the firewall between rich and poor countries that has guided the talks so far, but which the U.S. and other developed countries say must be removed going forward.

``We are now on our way to the new regime,'' European Climate Commissioner Connie Hedegaard said. It definitely wasn't an easy ride, but we managed to cross the bridge.''

``Hopefully from here we can increase our speed,'' she added. ``The world needs it more than ever.''

The goal of the U.N. talks is to keep temperatures from rising more than 3.6 degrees Fahrenheit (2 Celsius), compared to preindustrial times. Temperatures have already risen about 1.4 degrees Fahrenheit (0.8 Celsius) above that level, according to the latest report by the U.N.'s top climate body.

A recent projection by the World Bank showed temperatures are on track to rise by up to 7.2 Fahrenheit (4 Celsius) by the year 2100.

``For all of the nations wrestling with the new reality of climate change - which includes the United States - this meeting failed to deliver the goods,'' said Alden Meyer, of the Union of Concerned Scientists.

``At the end of the day, ministers were left with two unpalatable choices: accept an abysmally weak deal, or see the talks collapse in acrimony and despair _ with no clear path forward,'' Meyer said.

Poor countries came into the talks in Doha demanding a timetable on how rich countries would scale up climate change aid for them to $100 billion annually by 2020 _ a general pledge that was made three years ago.

But rich nations, including the United States, members of the European Union and Japan are still grappling with the effects of a financial crisis and were not interested in detailed talks on aid in Doha.

The agreement on financing made no reference to any mid-term financing targets, just a general pledge to ``identify pathways for mobilizing the scaling up of climate finance.''

Tim Gore, climate policy adviser at British aid group Oxfam said the Doha deal imperiled the lives and livelihoods of the world's poorest communities, who are the most vulnerable to shifts in climate.

``It's nothing short of betrayal of the responsibilities of developed countries,'' he said. ``We are now in the red zone in fighting climate change.''

Small island nations scored a victory by getting the conference to adopt a text on ``loss and damage,'' a relatively new concept which relates to damages from climate-related disasters.

Island nations under threat from rising sea levels have been pushing for some mechanism to help them cope with such natural catastrophes, but the United States has pushed back over concerns it might be held liable for the cleanup bill since it is the world's second-biggest emitter behind China. (AP)