World leaders will examine a successor to the Kyoto Protocol at a December summit in Copenhagen, Denmark.
U.N. officials expressed disappointment that slow progress in preliminary developments was endangering the potential for a comprehensive measure from Copenhagen.
EU officials blame hesitation from U.S. lawmakers and Beijing for undermining the effort to develop a new climate-change regime at the summit.
Piebalgs, the EU energy commissioner, hailed the signing of a bilateral trans-Atlantic energy agreement in October as a step in the right direction toward addressing the role that energy security has on climate change.
"By tackling issues such as the scarcity of fossil fuels or the development of clean energy technologies together, we will be able to find solutions and create opportunities for our businesses," he writes.
He warns, however, that both sides need to work together again at the Copenhagen summit.
"If the conference is to be a success, the U.S. and the EU will have to be able to find common ground," he said.