Computer hacker Gary McKinnon looks set to face trial in the US after Home Secretary Alan Johnson said there were no grounds to prevent his extradition.

Gary McKinnon, the man accused of hacking into the NASA and Pentagon IT systems in 2001 and 2002, has had been dealt another blow in his fight against extradition to the US.

McKinnon has Asperger's syndrome, but Home Secretary Alan Johnson has turned down an appeal to block the extradition on medical ground.

The hacker, who claimed to be looking for evidence of UFO activity faces 60 years in jail, if found guilty and up to two years in custody while awaiting trial.

The Home Secretary said it would not breach McKinnon’s human rights to send him for trial in the US, and so he had no power to prevent the extradition.

McKinnon’s lawyers will next week apply for a judicial review and, if necessary appeal to the European Court of Human Rights.

The powerful Home Affairs Select Committee of MPs earlier this month came out against McKinnon extradition.

In a letter to home secretary Alan Johnson, committee chairman Keith Vaz cited McKinnon's “precarious state of mental health”.

He wrote that “the committee is of the view that he should not be extradited to the USA and that you [Johnson] should exercise your discretion in this case”.

The call followed an evidence when McKinnon’s mother, Janis Sharp, warned that her son would “rather be dead” than sent for trial in the US.