In a startling move, a special prosecutor investigating the leak of a CIA operative’s identity retreated yesterday from an assertion that news outlets and critics of the administration seized on as evidence that President Bush and Vice President Cheney deliberately distorted a crucial intelligence summary on Iraq.

The prosecutor, Patrick Fitzgerald, claimed in a court filing last week that a former White House aide facing criminal charges for obstructing the probe, I. Lewis Libby, said he was told by Mr. Cheney to inform a New York Times reporter that one of the key judgments of a 2002 National Intelligence Estimate on Iraq was that the country was “vigorously trying to procure” uranium.

While the intelligence report indeed alleged that Iraq was aggressively seeking nuclear materials, that finding was not among the key judgments contained in the document’s early pages. The allegation that Mr. Cheney told Mr. Libby to misstate that fact to the Times journalist, Judith Miller, was noted prominently in some news accounts and contributed to an uproar that threw the White House into a tailspin last week.

However, in a letter yesterday, Mr. Fitzgerald advised the judge overseeing the case, Reggie Walton, that the government’s April 5 filing was inaccurate. “We are writing to correct a sentence,” Mr. Fitzgerald’s letter begins. He told the judge an error occurred in the following statement: “Defendant understood that he was to tell Miller, among other things, that a key judgment of the NIE held that Iraq was ‘vigorously trying to procure’ uranium.”

The prosecutor said the government brief should have said, “Defendant understood that he was to tell Miller, among other things, some of the key judgments of the NIE, and that the NIE stated that Iraq was ‘vigorously trying to procure’ uranium.”

The statements summarized by the prosecutor in last week’s filing and the new letter draw on testimony Mr. Libby gave to a grand jury investigating whether White House officials deliberately leaked the name of a CIA operative, Valerie Plame, to retaliate against her husband, Joseph Wilson, a former ambassador who challenged Mr. Bush’s public assessment of Iraqi nuclear weapons efforts.

Mr. Libby resigned as chief of staff to Mr. Cheney after being indicted in October on charges of obstruction of justice, perjury, and making false statements to investigators.

Mr. Fitzgerald’s letter to the court, which was obtained last night by The New York Sun, offered no explanation for the error in the earlier filing. A spokesman for the prosecutor, Randall Samborn, said he was not authorized to comment on the development.

The reversal by Mr. Fitzgerald does not directly undercut the central disclosures in last week’s government brief, namely that Mr. Libby told a grand jury that Mr. Cheney said he sought Mr. Bush’s approval for the disclosure of information from the intelligence estimate to Ms. Miller and that the declassification took place without the knowledge of officials, such as the director of central intelligence, who were embarked on a parallel but slower-moving effort to review the report for declassification.

However, the prosecutor’s revised account may disarm those who accused Messrs. Bush and Cheney of propagating a lie about the report’s findings. The now-withdrawn assertion that Mr. Libby was ordered to tell a reporter that a secondary and disputed finding in the report was, in fact, a “key judgment” was featured in the second paragraph of a front-page New York Times story on Sunday arguing that the leak to Ms. Miller was skewed.

A related claim, that the officials omitted from their presentation to Ms. Miller the reservations of some intelligence agencies, may still be plausible, even in light of Mr. Fitzgerald’s latest statement.

White House officials have declined to comment on the details of the declassification process, citing Mr. Fitzgerald’s request that witnesses in the case not speak publicly.

Over the weekend, an attorney involved in the case told the Associated Press that, while Mr. Bush approved declassification of the intelligence estimate, he was not aware of how Messrs. Cheney and Libby planned to dole out the information.

According to court papers, Mr. Libby discussed the estimate with Ms. Miller during a meeting at a Washington hotel on July 8, 2003. The key findings of the report were officially declassified and released to the press and the general public 10 days later.