President Bush's pick for attorney general has promised to fire any Justice Department employee who discusses sensitive cases with the White House without his approval, a leading Democratic senator said Thursday.

Earlier this week, retired federal judge Michael Mukasey told another senator he also would fire employees who failed to report being asked about cases by politicians, such as elected lawmakers.

The pledges were part of Mukasey's attempts to soothe critics, including those in Congress, who believe the Justice Department has become too close to White House politics.

At a Senate Judiciary Committee meeting Thursday, Chairman Patrick Leahy recounted asking Mukasey during a private meeting about White House meddling in criminal and civil cases.

"And he said, 'I'll tell you right now, if anybody calls any member of the Justice Department, if I'm attorney general they'll be given two numbers: It'll be the telephone number of the attorney general and the telephone number of the deputy attorney general. And they'll be told that if they want to talk to anybody, these are the only two people who can talk about this case. And we may well not talk about it,' " Leahy, D-Vt., quoted Mukasey as saying.

Mukasey continued by adding that if a Justice Department employees discusses cases "with somebody outside, whether from the White House or members of Congress or something else like that, they will be fired," Leahy recalled.

"That's the kind of attitude I like," he said.

Bush nominated Mukasey Monday to replace former Attorney General Alberto Gonzales, who resigned amid investigations into, among other things, whether the Justice Department had let politics influence decisions to hire or fire employees.

The inquiries were largely driven by accusations that nine U.S. attorneys who were fired in an unusual midterm purge last year were ousted because they were not "loyal Bushies," as Gonzales' former staff chief put it.

The topic surfaced Thursday as the Senate panel approved legislation limiting the number of Justice Department and White House employees who are authorized to discuss sensitive criminal and civil cases.

Documents show such discussions during the Clinton administration were restricted to six people -- two at Justice and four at the White House.

In 2002, a year after Bush took office, the number of people to get such authorizations was greatly expanded. According to estimates by Sen. Sheldon Whitehouse, D-R.I., 42 Justice Department employees were allowed to discuss sensitive cases with as many as 900 White House staffers.

Whitehouse, a former U.S, attorney, wrote the bill that passed the Senate panel by a bipartisan, 13-2 vote. It limits those discussions to the Justice Department's top three officials and four people at the White House: the president, vice president, and presidential counsel and counselor.