But Michele A. Flournoy, the under secretary of defense for policy, said of the detainees: “I think there will be some that need to end up in the United States.”

Pentagon officials said there had been no pressure from the Obama White House to suppress the report about the Guantánamo detainees who had been transferred abroad under the Bush administration. The officials said they believed that Defense Department employees, some of them holdovers from the Bush administration, were acting to protect their jobs.

The report is the subject of numerous Freedom of Information Act requests from news media organizations, and Mr. Whitman said he expected it to be released shortly. The report, a copy of which was made available to The New York Times, says the Pentagon believes that 74 prisoners released from Guantánamo have returned to terrorism or militant activity, making for a recidivism rate of nearly 14 percent.

The report was made available by an official who said the delay in releasing it was creating unnecessary “conspiracy theories” about the holdup.

A Defense Department official said there was little will at the Pentagon to release the report because it had become politically radioactive under Mr. Obama.

“If we hold it, then everybody claims it’s political and you’re protecting the Obama administration,” said the official, who asked for anonymity because of the sensitivity of the situation. “And if we let it go, then everybody says you’re undermining Obama.”

Previous assertions by the Pentagon that substantial numbers of former Guantánamo prisoners had returned to terrorism were sharply criticized by civil liberties and human rights groups who said the information was too vague to be credible and amounted to propaganda in favor of keeping the prison open. The Pentagon began making the assertions in 2007 but stopped earlier this year, shortly before Mr. Obama took office.