The Obama administration said Thursday that it needs two more months to review an internal CIA report on the agency's secret detention and interrogation program before making it public.

The Justice Department originally had said it intended to release the report in June as part of a lawsuit, but department officials now say they need until the end of August.

The report by the CIA's inspector general questioned the effectiveness of harsh interrogation methods, such as waterboarding, employed by CIA interrogators during the administration of former President George W. Bush.

Justice Department spokeswoman Tracy Schmaler said the report contains information that overlaps with other CIA documents that also must be reviewed for release by a court-ordered Aug. 31 deadline.

"As we re-reviewed the CIA IG report, it was clear that we would not be able to complete it in an expedited manner as we had hoped," Schmaler said. "There are unique processing issues to this review that made it clear to us we would need all the time the court gave us to complete it."

The government published a version of the report in 2008, but its contents were almost entirely blacked out. The American Civil Liberties Union filed a Freedom of Information Act lawsuit for release of all documents related to the interrogation program.

On June 3, a federal judge gave the administration until Aug. 31 to release 319 documents related to the program, and the Justice Department initially said it would expedite review of the inspector general report and turn it over in June. The report, more than 200 pages long, had been expected to be made public two weeks ago but was held back over debates about how much of it should be censored.

Department attorneys said in a letter to U.S. District Judge Alvin K. Hellerstein that they are not able to expedite the release of the report because they first need to review the other 318 documents to determine what needs to be blacked out.

"Given the sensitivity of the information at issue, and the need for coordination among multiple components of the government, the review of the remanded documents is a time-consuming and labor-intensive exercise," the government attorneys wrote.