US Attorney General Alberto Gonzales has defended the treatment of terrorism suspects held at the US military base at Guantanamo Bay.
Alberto Gonzales said he was in the UK to "provide reassurance"
Speaking on a visit to the UK, Mr Gonzales denied prisoners at the camp in Cuba had been tortured.
He told the BBC that of thousands of allegations of mistreatment, only five had been found to be genuine.
He also denied the US had used airports in Europe to transfer prisoners to countries where they would be tortured.
Last month a UN report called for the prison camp at Guantanamo Bay to be closed immediately, saying prisoners had no access to justice and were subjected to treatment that amounted to torture.
Mr Gonzales said his message to critics was "we hear what you're saying".
"We are aware of your concerns, we are here to communicate exactly what's going on in Guantanamo," he said.
"If there are alternatives, we are always willing to look at that."
'Interests of America'
In an interview with the BBC, Mr Gonzales said the detention camp was necessary in the interests of America and was consistent with the provisions of the Geneva Convention, which deals with the treatment of prisoners of war.
Allegations of mistreatment at the camp surfaced early on
He would not say whether the US government planned to close the camp.
"We have been and continue to reassess all of our activities in the war on terrorism to ensure they are in fact effective and to ensure they are in fact lawful," Mr Gonzales said.
The attorney general said only five cases of torture had been verified at Guantanamo Bay.
He acknowledged some people had a different interpretation of what constituted torture.
"There is a disagreement about what constitutes cruel, inhumane or degrading treatment. The notion that you can't embarrass or insult someone, I would question if that makes sense today," he said.
Mr Gonzales also said the relevance of some provisions of the Geneva Convention were questionable in respect to "this new kind of war, against this new kind of enemy".
"I'm not talking about the basic provision of human dignity - I'm talking about provisions that say you have to provide these detainees with commissary privileges, a monthly allowance - I think the average British citizen would say that sounds rather strange."
Mr Gonzales said the US respected the sovereignty of every European country when asked if rendition flights had moved through UK airspace or UK airports without the government's permission.
The UK government has said there have been no requests for such flights since 11 September 2001.
"We do not render individuals where we believe it's more likely than not that they will be tortured," Mr Gonzales added.
Mr Gonzales also said he wanted to see the UK-US extradition treaty ratified as soon as possible.
The UK government is unhappy their parliament has ratified the treaty, but the US Senate still has not - which makes extradition easier for prosecutors in the US than in the UK.