President Trump complained Tuesday that a Justice Department report being prepared on its handling of the Hillary Clinton email investigation is “taking so long” and said he hopes it is not being weakened.

In coming weeks, the department’s inspector general, Michael E. Horowitz, is expected to release a nearly 500-page report criticizing the Justice Department and FBI for their handling of the probe into Clinton’s use of a private email server while secretary of state, according to people familiar with the matter.

The report is certain to provide Trump fodder for his criticism of federal law enforcement as the Russia investigation continues and for his ongoing war of words with James B. Comey, the FBI director whom Trump fired and who oversaw the Clinton email investigation.

“What is taking so long with the Inspector General’s Report on Crooked Hillary and Slippery James Comey,” Trump wrote on Twitter. “Numerous delays. Hope Report is not being changed and made weaker! There are so many horrible things to tell, the public has the right to know. Transparency!”

During the 2016 campaign, Comey drew scrutiny for his decisions to publicly exonerate Clinton, the Democratic nominee, in the probe and to announce that he was reopening the investigation shortly before the election.

A draft of the inspector general’s report has been completed, and — as is typical for such reports — those people whose accounts are key to the findings have been given an opportunity to review the document and provide feedback.

That feedback could change the report, if the inspector general determines that any of his facts or conclusions were wrong. Typically, the final product comes after extensive negotiations, and the inspector general will often note where those he targeted disagreed with his assessment.

Trump’s tweet might put pressure on Horowitz to hold his ground if Comey, former deputy director Andrew McCabe and others push him to soften his conclusions.

However, the president’s weighing in could allow Comey, McCabe and others to charge that the inspector general’s work was politicized, and that could raise questions about his conclusions.

McCabe did just that when he was targeted by a separate report that accused him of lying to investigators about a media disclosure. The report came after the president had attacked McCabe for months, and Trump took to Twitter to celebrate it.

Contrary to what the president’s tweet suggests, the latest report is unlikely to criticize Clinton.

The inspector general was tasked with reviewing the decisions of those who investigated Clinton, not reinvestigating the former secretary of state herself.

Some supporters of Clinton have welcomed the inspector general’s review, as they were critical of Comey’s handling of the case. Clinton has argued that Comey’s unusual decision to reveal publicly on the eve of the election that investigators had resumed their work cost her the election.

Horowitz was appointed to the inspector general’s job in 2012 by President Barack Obama. He had worked previously as a white-collar-defense attorney at Cadwalader, Wickersham & Taft, as a prosecutor in the Southern District of New York and as a high-ranking official in the Justice Department’s criminal division.

Josh Dawsey contributed to this report.