HOME Secretary Alan Johnson has said he would be breaking the law if he blocked computer hacker Gary McKinnon's extradition.
Mr McKinnon, who suffers from Asperger's syndrome, lost a High Court bid to avoid being extradited to the US on Friday.
He could face a sentence of up to 60 years in a high-security prison if he is convicted.
Previous Home Secretary Jacqui Smith formally agreed to Mr McKinnon's extradition in October last year.
Mr Johnson said: "It would be unlawful for the Home Secretary to intervene."
Mr McKinnon, formerly from Palmers Green, has always admitted he hacked into high security Government and military computer systems from his flat but claims he was simply looking for evidence of UFOs.
His family fear he would not survive with his condition in the tough high-security US prison system.
Mr McKinnon's lawyers said he would appeal against the decision.
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