Washington (CNN) -- Embattled Nuclear Regulatory Commission Chairman Gregory Jaczko announced Monday he is resigning.
Jaczko, a former top aide to Senate Majority Leader Harry Reid, D-Nevada, has been under fire after complaints from Democrats and Republicans on the commission about his management style surfaced last year.
In his statement Monday, Jaczko said he would stay on until a successor is confirmed. However, election year politics make it unclear if the deeply divided Senate will be able to agree on a successor before the November election.
Last month, Jaczko denied allegations that he targeted women and created a hostile work environment. The accusations came amid a political fight between Congress and the White House over who should serve on the five-member commission that oversees the nation's nuclear industry regulation.
Jaczko has been portrayed as nuclear energy expert who has tried to push the commission to tighten safety standards, which the nuclear power industry opposes. He served on the panel for almost eight years, including three as chairman.
White House assistant press secretary Clark Stevens said President Barack Obama appreciated Jaczko's efforts at the NRC.
"A strong and effective NRC is crucial to protecting public health and safety, promoting defense and security, and protecting the environment, and we intend to nominate a new chairman soon," Stevens said.
Rep. Darrell Issa, R-California, who chairs the House Oversight and Government Reform Committee, said Jaczko's resignation closed an "ugly chapter" at the commission.
"This was never about nuclear safety, but rather poor leadership that created an abusive and hostile work environment," Issa said.
Reid, however, praised Jaczko for improving the safety of nuclear energy during his tenure on the commission.
"I am confident whomever replaces Chairman Jaczko will share his commitment to protecting the safety of the American people over the interests of a single industry," Reid said in a statement. "This is an opportunity for the nuclear industry to demonstrate its commitment to public safety by supporting a chairperson who puts the safety of American citizens first."