Updated

The Obama administration has tightened restrictions on media access to the Guantanamo military prison since June, a change that sources suggest stems from incidents in which some Chinese Muslims being detained there compared the U.S. government to China and Nazi Germany.

Reporters who cover military commissions in the courtroom can no longer tour the prisons on the same trip.

The move has drawn criticism from lawmakers who say that policy is at odds with the Obama administration's pledge of transparency.

"Nothing is transparent over there," Sen. James Inhofe, R-Okla., told Fox News.

The controversy comes as the Senate approved a plan Tuesday to permit Guantanamo detainees to be shipped to U.S. soil to face trial, helping Obama in his effort to close the facility by January.

Also on Tuesday, the Supreme Court agreed to decide whether detainees who are considered no threat can be ordered released in the United States over the objections of the Obama administration and Congress if the prisoners have nowhere else to go. The case will focus on 13 Uighurs, most of whom were cleared by the Pentagon for release in 2003.

In June, during a press tour of the detention camp, some of the Uighurs approached the fence around the facility and, with phrases written on an art pad, compared the U.S. government to that of China and Nazi Germany. One Uighur asked in English, "Obama is a communist or a Democrat?"

That incident was highly embarrassing for both the White House and the Pentagon, multiple sources told Fox News.

Inhofe, a senior Republican on the Armed Services Committee, sent a letter to the White House questioning whether there is a change in policy that now limits the media.

"It now appears that members of the media must plan, schedule and fund separate trips to cover either the military commissions or the detention facility," Inhofe wrote. "This directly impacts worldwide press access to Gitmo."

While candidate Obama promised transparency nine months into his term, the president's own supporters on the left seem deflated. In a recent interview at the military base, the ACLU said efforts to limit media coverage grate against the administration's own pledge.

"Members of the media have an important role to play in informing the American public about whether or not the conditions of confinement are actually humane, asking the questions, seeing with their very own eyes," ACLU Executive Director Anthony Romero said. "Taking the government's word for it is just not sufficient."

A Pentagon spokesman didn't directly address whether the policy has changed.

"I'm not so sure the policy has changed," Pentagon spokesman Geoff Morrell said at a news conference. "If Fox is having a particular issue getting an opportunity to go down there and see the detention facilities for the 100th or 150th time, I'd be happy to try to work with you to figure out an opportunity to do so, OK?"

Fox News' Catherine Herridge and The Associated Press contributed to this report.