Turning aside an urgent White House appeal for the second time in a month, Chief Justice William H. Rehnquist cleared the way Tuesday for prosecutors to question White House lawyers about their advice to President Clinton in the Monica Lewinsky case.

Rehnquist refused to postpone a federal appeals court ruling that White House lawyers could not invoke attorney-client privilege and must answer questions before a federal grand jury investigating an alleged presidential affair and cover-up.That ruling involved presidential lawyer and confidant Bruce Lindsey, who as a result of Rehnquist's decision will have to testify after he completes his recovery from back surgery last week.

Another White House lawyer, Lanny Breuer, was subpoenaed to appear before the grand jury and arrived at the courthouse Tuesday. "My plan is to go up to the grand jury room," Breuer said. Asked about the fuss over his testimony, he laughed and said, "I'm honored."

The court rulings on the last-ditch effort to block Lindsey's testimony left open the possibility that Breuer could also refuse to answer questions on the grounds of attorney-client privilege like Lindsey.

If Breuer did so, prosecutors would have to go to U.S. District Judge Norma Holloway Johnson, who oversees the grand jury, and seek to compel him to answer. The White House would then have the option of going back to the federal appeals court and Rehnquist seeking a stay of his testimony.

Breuer has helped the White House respond to subpoenas in various investigations. Legal sources said he wasn't expected to possess much firsthand information about the relationship between Lewinsky and the president.

But prosecutors probing possible obstruction of justice and witness tampering wanted to question him about what he may have observed in the early days of the Lewinsky controversy when the White House sought to contain damage.

Rehnquist handles emergency matters from the District of Columbia for the Supreme Court. Lawyers for the White House now have the option of seeking help from any one of the eight other Supreme Court members, but there was no word whether they would do so.

"There is some disappointment here about that decision," White House spokesman Barry Toiv said after Rehnquist's decision. "This is a very important principle that we will continue to pursue."

Toiv said the White House concern was not about "one or more people testifying" but rather "the ability of not just this president but more importantly future presidents to have the benefit of the attorney-client privilege, which is a bedrock of our legal system."

Rehnquist had on July 17 rejected a similar effort to protect Secret Service officials from having to testify before the same grand jury.

A federal appeals court on Monday turned down a White House request to stop prosecutors from questioning presidential lawyers, including Lindsey, the Clinton confidant at the center of the months-long legal fight over the legal doctrine known as attorney-client privilege.

Rehnquist had been asked to temporarily block such testimony until the Supreme Court considers whether government lawyers enjoy the same attorney-client confidentiality as private attorneys.

Tuesday's action is another victory for independent counsel Ken-neth Starr, who is pressing to wrap up his investigation into an alleged presidential affair and cover-up.

Lindsey, the White House deputy counsel and one of Clinton's closest and oldest friends, is recovering from back surgery.

The White House has been arguing unsuccessfully that lawyers such as Lindsey and Breuer should not be forced to testify about their conversations with Clinton because it would violate the president's right to seek confidential legal advice.