German Chancellor Angela Merkel called on Monday for movement by India and China at the world climate summit.
Speaking in a special news broadcast on Germany's ZDF public television, she said big emerging economies had not offered enough.
"India and China in particular must offer more," she said, noting that the US had already accepted the objective of limiting global warming to 2 degrees Celsius by 2050.
She said she would keep working to persuade conference nations right up to the last minute to adopt mutually agreed targets. The summit in Copenhagen opened on Monday.