President Obama is preparing to nominate James Comey, a former deputy attorney general in the President George W. Bush administration, as the next director of the FBI, although a formal announcement could be weeks away, sources with knowledge of the decision told ABC News.

Comey served as deputy attorney general from 2003 to 2005. If confirmed by the U.S. Senate, Comey would succeed outgoing FBI Director Robert Mueller, who has led the agency since 2001.

Comey was serving as acting attorney general in 2004 when Attorney General John Ashcroft went into intensive care. During that time, Comey faced a tense standoff when White House Chief of Staff Andy Card and White House counsel Alberto Gonzales visited the ailing Ashcroft's hospital room to try to obtain reauthorization of the administration's terrorist surveillance program.

Comey, 52, also threatened to resign from his post if the administration resumed wiretapping without the Justice Department's approval.

Following his post at the Department of Justice, Comey worked for Lockheed Martin Corp. and Bridgewater Associates. Prior to serving as deputy attorney general, Comey was the U.S. Attorney for the Southern District of New York and served as the managing assistant U.S. attorney in charge of the Richmond Division of the U.S. Attorney's office for the Eastern District of Virginia.

Comey is a graduate of the University of Chicago Law School.