Britain has agreed to extradite Gary McKinnon, who allegedly hacked into US defence computer systems in what has been dubbed the "biggest military hack of all time", the home office said.
"On July 4 the Secretary of State (John Reid) signed an order for McKinnon's extradition to the United States for charges connected with computer hacking," a home office spokesman said on Thursday.
Using software available for download on the Internet, McKinnon allegedly hacked into computer networks operated by NASA, the US Army, US Navy, Department of Defense and the US Air Force from 2001 to 2002 in what the Virginia state prosecutor said was the "biggest military hack of all time".
McKinnon was indicted in November 2002 by a federal grand jury in Alexandria, Virginia on seven counts of computer fraud and related activity, the US justice department said on its website.
"McKinnon had exercised his right to submit representations against return but the Secretary of State did not consider the issues raised availed McKinnon," the home office (interior ministry) spokesman said. "McKinnon now has the opportunity, within 14 days, to appeal against the decisions of the district judge/Secretary of State."
McKinnon told BBC News 24 he was planning to appeal the decision, adding: "I am very worried and feeling very let down by my own government."
A British court had decided in May that McKinnon should be extradited, but the case went for a final decision to the home office.