U.S. emissions target "protectionist": German minister

"The American position has certain protectionist aspects, so they want to avoid a level playing field because they are afraid that we are front runners in this competition," said Norbert Rttgen, referring to the race to shift away from carbon-intensive fossil fuels.

"The Chinese are not very interested in a level playing field either," he added.

With vibrant solar and wind power sectors, Germany ranked third in renewable energy in 2009 according to Ernst & Young, behind both the U.S. and Chinese for the first time.

Delegates from over 190 countries meeting in the Danish capital have scant time to iron out a new global climate pact before 110 world leaders descend on the talks later this week.

President Barack Obama has pledged to cut U.S. emissions by 17 percent below 2005 levels by 2020, equivalent to 4 percent below the more common 1990 baseline used by the Kyoto Protocol.

China said it will reduce its carbon intensity -- the amount of carbon dioxide emitted for each unit of GDP -- by 40 to 45 percent by 2020 compared to 2005 levels.

In contrast, German Chancellor Angela Merkel earlier this year announced a plan to cut emissions by up to 40 percent by 2020 if a tough treaty is signed in Copenhagen.

"There is a sincere concern by other countries that developed countries intended to delude the legal character of our commitments," Rttgen said.

"We've reached a critical stage ... My view is we will achieve legally-binding commitments on Friday."

"We have a moral duty to be successful."