Former White House counsel Kathryn Ruemmler has told President Barack Obama she doesn't want to be nominated for attorney general, after he asked her to consider succeeding Eric Holder, people familiar with the discussions told The Associated Press on Friday.

Ruemmler was concerned that her experience as a close adviser to the president would have led to a difficult confirmation process in the current highly charged partisan environment, the sources said, speaking on a condition of anonymity because they were not authorized to discuss private discussions. They say Ruemmler, a top official at the Justice Department before moving to the White House, was also concerned that could ignite political attacks against Obama.

Ruemmler's withdrawal, in a phone call to the president Wednesday, leaves no obvious front-runner to replace Holder, who announced a month ago that he would step down once a replacement was confirmed. Ruemmler brought the law enforcement bonafides of a former prosecutor in the Bush administration who won convictions against Enron's executives and the national security expertise of a top White House official.

Other candidates that administration officials have said have been considered include Solicitor General Don Verrilli; Labor Secretary Tom Perez; Loretta Lynch, U.S. attorney for the Eastern District of New York; Preet Bharara, U.S. attorney for the Southern District of New York; Jenny Durkan, who resigned as U.S. attorney in Washington state last month; former Homeland Security Secretary Janet Napolitano; Tony West, who recently resigned as the No. 3 official at the Justice Department and has taken a job at Pepsico; and Deputy Homeland Security Secretary Alejandro Mayorkas.

Ruemmler, now a partner at Latham & Watkins specializing in government investigations, had the closest relationship of the attorney general candidates to the president after serving as his legal gatekeeper at the White House. But that relationship also would have brought tough scrutiny, with Republicans likely to question her handling of controversies involving the IRS, Benghazi and the investigation of a White House volunteer in a prostitution scandal.

Obama's aides say he has not yet made up his mind on whom to nominate and won't announce a choice until after the Nov. 4 elections, in part to avoid making the nominee into a political issue facing embattled Democratic candidates. They say he also hasn't decided whether to seek confirmation in the Senate's lame duck session later this year or to wait until the new year, when Republicans are expected to pick up seats if not win outright control.

White House chief of staff Denis McDonough said in a statement, "Kathy is someone who always tells it like it is, is a world class lawyer and remains a trusted adviser to the president. Anyone who knows Kathy knows she has impeccable judgment, extraordinary foresight and is a formidable force. But she is also as selfless as they come, and the president is proud to call her a close friend."