Merkel, Brown accept Copenhagen deal, wanted more

Merkel said she would support the compromise despite mixed feelings. "The decision has been very difficult for me. We have done one step, we have hoped for several more," she said.

She added that the deal was not ambitious enough for the European Union to increase its commitment to cut carbon emissions by 30 percent by 2020 from 20 percent.

"We have made a start," Brown told a news conference. "What we need to follow up on quickly is ensuring a legally-binding outcome."

"..I know that we will need a legally-binding treaty over the next period of time if we are to secure all the commitments, particularly the years after 2020," he said.

(Reporting by Peter Griffiths and Markus Wacket)