(CNN) – It's been nearly three weeks since word broke that President Obama planned to nominate James Comey to replace retiring Robert Mueller as FBI director.
But as of Wednesday, the White House hadn't made any moves on announcing Mueller's successor. His term ends in September, and with Congress out of town for much of August, that doesn't leave much time for the Senate to consider the president's nominee.
Sen. Chuck Grassley, R-Iowa, raised the point Wednesday at a Senate hearing, and asked Mueller if he had any idea when they can expect the White House to announce his pick.
"I do, but I'm not in a position to be able to (inform) the committee," Mueller said.
The FBI director added that the administration has been preparing for a transition for the past two and a half years. "We are prepared to start the briefings as soon as the person is sworn in."
Comey served as a deputy attorney general in President George W. Bush's administration beginning in 2003.
He's perhaps best known for his testimony to a Senate committee in 2007, when he said he considered resigning his high-profile administration position over a disagreement about the National Security Agency's domestic surveillance program.
Officials familiar with the nomination process confirmed to CNN on May 30 that Comey was Obama's choice to head the FBI.
But White House Chief of Staff Denis McDonough sparked some intrigue Sunday when he referred to Comey as one "among many other people" who had been considered for the job.
"It's precisely because of his views on things like surveillance that I think he's come to the president's attention," McDonough said on CBS' "Face the Nation."
But the following week, the NSA–the same agency with which Comey had issues–was in the headlines after a contractor leaked information about two of the agency's massive surveillance programs.
Facing pushback from some who raised privacy concerns, Obama staunchly defended the programs shortly after they became known to the public. He described the NSA's work as "modest encroachments on privacy" that help prevent terrorism, but also repeatedly acknowledged that the country needs to have a debate over privacy vs. civil liberties.
The White House did not respond to a request for comment.
– CNN's Ashley Killough contributed to this report.