President Obama's chief climate adviser is stepping down from her post as the administration moves ahead with the centerpiece of Obama's ambitious green-energy agenda.

Obama chief of staff Denis McDonough announced Monday that Heather Zichal, the president's top climate adviser for the last five years, is leaving the White House.

“Heather will be missed here at the White House, but our work on this important issue will go on,” McDonough said. “We will continue to make important progress in reducing carbon pollution to help keep our air and water clean and protect our kids, helping communities prepare for a changing climate and leading international efforts to address climate change.”

McDonough did not elaborate on when Zichal would leave the White House or who would replace her.

Zichal was a major player in the administration's efforts to crack down on carbon emissions.

The Environmental Protection Agency recently unveiled new rules that would force future power plants to significantly cut down on their carbon footprint. Republicans have dismissed the first-ever regulations as part of the administration's “war on coal.” The administration next June is expected to roll out new rules for current power plants, restrictions long seen as the foundation of Obama's plan to combat climate change -- and sidestep Congress.

The White House did not comment on Zichal's future plans.