The Mayor of London has accused the Home Secretary of "passing the buck" by failing to intervene to prevent the extradition to America of computer hacker Gary McKinnon.

Writing in a national newspaper, Boris Johnson said the authorities' refusal to stop his removal will count as "one of the most protoplasmic acts of self-abasement since Suez".

Home Secretary Alan Johnson yesterday came under fire from the 43-year-old hacker's mother, Janis Sharp, after he said in a newspaper article Mr McKinnon was accused of hacking computers "shortly after the attacks of 9/11".

Mr McKinnon, who suffers from Asperger's Syndrome, is wanted for trial on charges of hacking into US military networks.

Supporters say he is a "UFO eccentric" who looked for evidence of extra-terrestrials.