Congressman Dennis Kucinich (D-OH) has been unable to visit with Private Bradley Manning, the U.S. soldier accused of leaking State Department cables to WikiLeaks, despite being a member of the House Committee on Oversight and Government Reform.

"I put in a request to the secretary of defense, who referred me to the secretary of the army, who referred me to the secretary of the navy, who referred me to the secretary of defense, and still not an answer on whether or not I can visit Private Manning," Rep. Kucinich explained to radio host Scott Horton on KPFK 90.7 FM Los Angeles, during Friday's broadcast of Antiwar Radio.

He previously announced he would visit Manning to investigate reports that he had been subjected to abuse while in custody.

Manning attorney David Coombs revealed last week that for at least two nights in row, the Army private had been "stripped naked" for as long as seven hours at a time.

In the mornings, he was left without clothes and forced to stand at attention.

"No one held prisoner anywhere in America should be tortured," Rep. Kucinich told Horton. "And the fact that he’s awaiting trial and they’re doing this to him raises serious questions about our criminal justice process. And I’m going to continue my efforts to address the plight of Private Manning and to try to stop this outrageous treatment of him."

Manning has been held at the prison since July under a maximum security regimen, which leaves him in his cell for 23 hours a day, because authorities say his escape would pose a risk to national security.

The army private faces numerous charges for stealing classified files and is suspected as the source of a massive trove of classified documents published on the WikiLeaks website in recent months, infuriating and embarrassing US officials.

The Pentagon earlier rejected allegations of harsh conditions and said Manning received treatment similar to others under the high-security regime.

"He's not being treated differently than any other maximum security detainee and not differently really that much from the medium security detainees," Pentagon press secretary Geoff Morrell told MSNBC after he paid a visit to the site himself.

"The Secretary of Defense has a grave responsibility here because he’s acting in the administrative capacity of the highest responsibility," Rep. Kucinich said. "He’s acting in the president’s stead as a member of the president’s cabinet handling defense matters."

"He has a very grave responsibility here, and this thing – you know, if these reports keep coming out and they do not permit third parties to come in and make an assessment, I don’t think that we can take their word for it. We just can’t."

With prior reporting by David Edwards