WASHINGTON (AP) _ As President Clinton's aides dampened speculation that he would change his story about Monica Lewinsky, the White House waged a last-ditch effort Monday to block prosecutors from questioning its lawyers by seeking an emergency order from Chief Justice William Rehnquist.

A federal appeals court refused to issue such an order as the months-long battle over whether White House deputy counsel and presidential confidant Bruce Lindsey can refuse to testify on grounds of attorney-client privilege reached its last avenue of appeal in the Supreme Court.

With Lindsey recuperating from back surgery, the White House's more immediate concern was for another one of its lawyers, Lanny Breuer, who was subpoenaed and ordered to testify on Tuesday before the grand jury investigating an alleged presidential affair and coverup.

Breuer, who has been instrumental in preparing document requests in response to subpoenas, is expected to appear as ordered. But legal sources, speaking on condition of anonymity, said he wasn't expected to offer much insight on the relationhip between Clinton and Ms. Lewinsky, a former White House intern.

The administration want to block testimony by its lawyers until the Supreme Court decides this fall whether to consider the legal issue of whether government employees like Lindsey enjoy the same attorney-client confidentiality as private lawyers. A federal judge and appeals court have ruled against the White House.

The emergency request went to Rehnquist after the U.S. Court of Appeals for the District of Columbia turned down a similar appeal.

Rehnquist could decide alone whether to issue the emergency order, or send the matter to the full nine-member court. Even if the administration loses on the emergency order, it plans to ask the court to uphold the attorney-client protection for government lawyers in criminal cases.

A Supreme Court spokeswoman, Kathy Arberg, said Rehnquist was not expected to act Monday night.

At issue is a decision last month by a three-judge appeals court panel rejecting Lindsey's claim of attorney-client privilege and ordering him to testify before the grand jury investigating an alleged presidential affair and cover-up.

White House counsel Charles F.C. Ruff said the White House would bypass a chance to ask the full U.S. Court of Appeals to hear the case, instead sending its appeal directly to the Supreme Court to consider when it reconvenes in October.

``The attorney-client privilege is a bedrock principle of our legal system,'' Ruff said in a statement.

If the courts oblige, the move could delay Independent Counsel Kenneth Starr from questioning Lindsey for some time.

On a related matter, the U.S. Court of Appeals issued a sealed ruling that legal sources said permitted U.S. District Judge Norma Holloway Johnson to proceed with a hearing she ordered to determine if Starr improperly leaked grand jury evidence. But the sources said the ruling also addressed the prosecutor's concerns that the president's lawyers might gain access to sensitive evidence during the proceedings.

Legal sources familiar with the ruling, who spoke on condition of anonymity, said the court ruled the leaks investigation could proceed but that any evidence that is produced should be turned over and reviewed by Johnson.

David Kendall, the president's lawyer, has accused Starr of illegal leaks and requested that the prosecutor be sanctioned for contempt of court. Starr's office has denied releasing any information improperly.

Starr's prosecutors spent more time Monday preparing Ms. Lewinsky for her upcoming grand jury appearance. That could come as early as later this week or early next week, legal sources said.

At the White House, the presidents' advisers played down the possibility that Clinton would reverse previous statements and admit to a sexual relationship with the former White House intern, a strategy suggested by some Republicans and Democrats over the weekend as a way to avoid impeachment proceedings.

Clinton testified under oath in January in the now-dismissed Paula Jones sexual harassment lawsuit that he did not have sexual relations with Ms. Lewinsky. Ms. Lewinsky gave similar testimony then, but has reversed course and told prosecutors they did engage in sexual activities, legal sources say.

Starr's office is investigating whether Clinton lied under oath in the Jones case and conspired with Ms. Lewinsky and others to obstruct the investigation or cover up an affair. Clinton denies any wrongdoing.

``The president has told the truth about this and he will continue to do so,'' White House spokesman Barry Toiv said Monday. ``I have no reason to think that that has changed in any way.'''

One of Clinton's senior advisers, speaking on condition of anonymity, said that while Clinton's exact plans for his testimony are known only to his private lawyers, there was no preparation under way for a dramatic reversal.

``Nobody is sitting around here going through his deposition (from January) and saying, `We can shave here, and we can switch stories there,''' the adviser said.

An outside adviser to the White House acknowledged, however, that much of Clinton's inner circle remained anxious to learn the results of FBI tests on a dress Ms. Lewinsky provided to prosecutors, which she claimed contained a stain from a 1996 sexual encounter with the president.

If the tests link the stain to Clinton through DNA testing, it would become a dramatic piece of new physical evidence that would alter any plans now on the table, the outside adviser said.

``There is some anxiety, and aides are essentially in suspended animation until they know what happens. And those tests will drive any final decision that is made,'' the outside adviser said, speaking on condition of anonymity.

The FBI and Starr's office were mum on the results of any tests.

Toiv said Clinton ``will spend a fair amount of time talking to his lawyers'' in the next two weeks before he talks by closed circuit television to the grand jury on Aug. 17.