Europe's biggest economy also faces resistance from outside the bloc, notably from the United States, on global efforts.

Gabriel, unveiling Germany's plan to combat the problem to parliament, said it was time to act.

"We have all witnessed the dangers of climate change in the last few months. We only saw winter in the calendar in Germany," he told the lower house of parliament.

The Social Democrat minister raised the target for the share of electricity to be sourced from wind, hydro-electric or solar power to 27 percent by 2020 from 12 percent currently.

Boosting green power output this way would cut German carbon dioxide (C02) emissions by 55 million tonnes compared to 2006, said Gabriel, and reducing electricity consumption 11 percent via greater efficiency would save 40 million tonnes of CO2.

"These measures are very ambitious -- but doable," said the minister. "We are taking the implementation of climate protection goals seriously for the first time."

Gabriel also said he would boost the amount of heating in buildings that comes from renewable energy and double the number of combined heat and power plants that trap and reuse heat generated in power production rather than releasing it.

He said his plans would cost about 3 billion euros (US$4.1 billion) by 2010.

Environment protection groups, including Germany's BUND, welcomed the plans, which they described as ambitious, but cautioned that words had to be turned into deeds.

G8 ACTION

Gabriel also said it was essential for other countries, notably the United States and developing nations, to act.

The EU has agreed to reduce its C02 output by 20 percent by 2020 from 1990 levels and if other industrial and emerging nations support the drive, the 27-member bloc envisages raising the target to a 30 percent reduction.

Chancellor Angela Merkel wants progress at a June G8 summit in Germany but US President George W. Bush is reluctant to commit to curbing greenhouse gas emissions.

"If we succeed in breaking the deadlock between the United States and some industrial countries on the one hand and developing countries on the other, the chances do not look bad. I am quite optimistic," Gabriel said.

Germany has said it could make a 40 percent cut if other nations support the EU drive, which would involve Germany cutting waste gas emissions by 270 million tonnes by 2020 compared to 2006.

To this end, Germany aims to raise the proportion of biofuels in use to 17 percent from five percent now.

Gabriel also reiterated his view that nuclear energy was not the answer to combating climate change.

The ruling coalition, between Merkel's conservatives and the Social Democrats, has agreed to continue the phasing out of Germany's atomic power plants agreed under the previous government even though conservatives favour nuclear energy.

Germany is building more coal-fired power stations.