BRUSSELS, Belgium (AP) - European Union leaders on Friday endorsed binding targets to cut greenhouse gases and ensure a fifth of the bloc's energy comes from green power such as wind turbines and solar panels.
The deal also noted the role nuclear power could play in tackling greenhouse gas emissions, an inclusion not welcomed by all leaders.
''We have time still to reduce global warming to below 2 degrees,'' Merkel said as she announced the plan that would require greenhouse gas emissions to be cut by at least 20 percent from 1990 levels by 2020 and ensure 20 percent of its power comes from renewable energy. ''We could avoid what could well be human calamity.''
Merkel said the agreement puts Europe at the forefront on the movement to combat global warming.
''This text really gives European Union policies a new quality and will establish us as a world pioneer,'' German Chancellor Angela Merkel said.
European Commission President Jose Manuel Barroso called the measures ''the most ambitious package ever agreed by any institution on energy security and climate change.''
Merkel led negotiations on details of the package, which also states that by 2020, the EU wants to ensure 20 percent of its power comes from renewable energy and 10 percent of its cars and trucks run on biolfuels made from plants.
European leaders hope their commitment to tackling climate change will encourage other leading polluters like the United States and China to agree on deep emissions cuts. Merkel plans to present those plans to a summit of the Group of Eight industrialized nations that she will host in June.
''It is important that we can tell the G-8 members that Europe has made a real commitment,'' Merkel said. ''That gives us a measure of credibility.''
Achim Steiner, executive director of the U.N. Environment Program, said the agreement would put the spotlight on the United States, the world's biggest emitter of greenhouse gases.
''The decision in Brussels puts an even greater level of attention on what will happen in the United States in the next few years,'' he said Nairobi, Kenya.
The deal represents a compromise between nations that had demanded mandatory targets on clean energy and eastern European nations led by Poland and Slovakia that had argued that they do not have the money to meet such high targets for developing costly alternatives and preferred to stay with cheaper, but more polluting options such as coal and oil.
While setting an overall 20 percent target for renewable energy, the agreement says individual targets will be allowed for each of the 27 EU members.
''A differentiated approach to the contributions of the member states is needed, reflecting fairness (and) taking into account national circumstances,'' the agreement says. It tasked the EU's executive Commission to establish national targets for each country.
It also mentions solidarity between EU nations in times of energy supply crises from suppliers such as Russia, as demanded by the Poles.
Many of the former Communist nations that joined the EU in 2004 lag behind their Western neighbors in developing clean fuel. Although their economies are growing fast, most are still struggling to catch up with the West and say they need more time to meet the 20 percent target.
Cooler, landlocked countries such as Slovakia, Hungary and the Czech Republic also argued that they were handicapped in developing wind, solar and water-based power sources, which recently gained wider use in countries such as Denmark and Spain.
The deal contains a reference to the role of nuclear power, a demand of the French, Czechs, Slovaks and others who argued it could play a crucial part in helping Europe move away from carbon fuels.
It says each EU nation should decide whether to use nuclear power, but takes note of a Commission report that says nuclear energy could contribute to reducing greenhouse gas emissions and help alleviate worries about security of energy supply. It also stresses the need to improve nuclear safety.
Austria, Ireland and Denmark did not want the EU to sanction nuclear power, and the German government is split over whether to develop atomic energy. ''Our Austrian attitude toward sustainable energy definitely does not include nuclear energy,'' Foreign Minister Ursula Plassnik told reporters.
Friends of the Earth said it was appalled by the mention of nuclear power.
''Nuclear energy is too expensive,'' said Jan Kowalzig, a campaigner with the group. ''Nations should invest more cleverly in developing other energy sources.''
He called the 20 percent target for renewables ''too low,'' but said the group was pleased it was binding.
The leaders also agreed that EU nations should forge a common approach in dealing with its main foreign supplies of energy. The EU hopes to intensify imports from central Asia and Africa to reduce reliance on oil and gas supplies from Russia. They also want to diversify energy supply routes, a response to recent problems that saw Russia turn off the taps on pipelines carrying oil and gas westward.
EU leaders asked regulators to develop a plan on opening the EU's internal energy market and overcoming problems such as overcharging and under-investment, which have been blamed for two major blackouts in the past year. They stopped short of endorsing a plan to split up national energy monopolies.
The EU's environmental agenda is to be pursued in parallel with commitments under the Kyoto Protocol, the U.N. treaty on climate change. The major EU economies have committed to cut greenhouse gases by 8 percent below 1990 levels by 2012, and want the United States to sign the treaty. The U.S. argues that Kyoto would hurt its economy and says the treaty should also apply to surging Asian economies like China and India.