UN special rapporteur on torture, Manfred Nowak's remark came in the backdrop of the WikiLeaks documents on Iraq, which indicated that US troops had handed over prisoners to Iraqi forces knowing that they could be tortured.

"President Obama, as his predecessor, has an obligation under the Convention of Torture to independently investigate every allegation of torture or suspicion of torture and there are plenty of allegations," Nowak said.

"A full investigation. Its not enough just now to investigate what happens in Iraq. We know what happens in Iraq. I think what we need is full investigation into torture practices by US officials," he added.

Noting that under regular laws, the US government is entitled to pay compensation for torture, but invoking the State Secrets' Protection Act had shielded them from doing so, Nowak said, "We don't have even one case where the US administration actually paid compensation to any of those victims".

Pointing out that to the best of his knowledge- torture was no longer being practiced in Guantanamo Bay and rendition camps under the present administration, Nowak said that he had not been allowed to individually interview detainees.

Nowak also pointed out that Obama had been stopped from closing Guantanamo Bay by forces inside the country and a lack of help from European nations.
"I still think he (Obama) is serious about that", he said.

Nowak further asserted that the WikiLeaks documents "confirmed allegations about the brutality and the torture systematically practiced by Iraqi security forces".
"It shows the Bush administration and the Obama administration know and do know when they are handing over detainees under US custody to Iraqi security forces that there is a serious risk of them being subjected to torture," he added, noting that it violated international law.

Nowark recommended that perpetrators of torture as well as their superiors need to be brought to justice, and investigations could be done by US officials with intervention from outside experts if needed.

"We deplore WikiLeaks for inducing individuals to break the law, leak classified documents and then cavalierly share that secret information with the world, including our enemies," said Geoff Morrell, the Defense Department press secretary.

Nowak, an Austrian university professor who has completed his six year term as UN rapporteur, reiterated that "Guantanamo Bay is illegal"