A federal electric grid regulator announced his resignation Thursday, a move that will add another new face to a body that's undergoing significant changes.

John Norris, a Democrat, will leave the five-member Federal Energy Regulatory Commission on Aug. 20 to take a position with the United States Agriculture Department in Rome, Italy.

"Earlier today, I submitted my letter of resignation from the Federal Energy Regulatory Commission to President Obama," Norris said in a statement. "It has been a great honor to serve with all the exceptional professionals and public servants who make up the FERC family and so many dedicated energy stakeholders in the public and private sectors."

Norris — a former Iowa Democratic Party chairman, whose wife served as Michelle Obama's chief of staff — wasn't due to leave FERC until June 2017.

Some had considered him a likely candidate to take over as FERC chairman, noting his ties to Obama. But the president, with insistence from Senate Majority Leader Harry Reid, D-Nev., nominated Norman Bay, who headed FERC's enforcement office. He will take the chairmanship from Cheryl LaFleur in April 2015 in a deal brokered by Reid, the White House and other lawmakers designed to assuage concerns about Bay's lack of commission experience.

As for Norris' potential replacement, SNL Financial reported that Colette Honorable, chairwoman of the Arkansas Public Service Commission who also heads the National Association of Regulatory Utility Commissioners, as the likely candidate.