The High Court in London yesterday rejected a move by Belgium and six human rights groups to block the release of the former dictator, Gen Augusto Pinochet.
However, Belgium immediately started an appeal against the judgment, ruling out any prospect of a swift conclusion to the 15-month wrangle over the general's fate.
Ruling in the High Court, Mr Justice Maurice Kay rejected the parties' application for judicial review of the Home Secretary's refusal to publish the medical reports which convinced him the 84-year-old general was unfit to stand trial. The judge said Mr Jack Straw had acted "lawfully, fairly and rationally" when he announced he was consequently minded to send the general back to Chile rather than extradite him to Spain to face torture charges.
Lawyers for the Belgian authorities started an appeal with the Crown Office of the High Court within hours of the hearing. They will renew their attempt for a judicial review before two or three judges in the Divisional Court next Monday.
The six human rights groups, including Amnesty International, are also considering whether to take the challenge further.
Mr Straw, who has said he will not make a final decision on the case while it is before the courts, is now expected to hold off until the hearing is completed.
The Chilean Air Force Boeing 707, which flew into RAF Brize Norton from Bermuda over the weekend in anticipation of an end to the saga, is expected to remain on the tarmac.
In his 37-page ruling, Mr Justice Kay said he was "completely against" the arguments put forward by the human rights groups that they should be given access to the medical report or be allowed to conduct another examination of the general.
Mr Straw had already obtained an "impartial" medical assessment of Gen Pinochet by an internationally distinguished team as required for him to carry out his public duties.
The general could not be compelled to undergo a medical examination, and had agreed to it only on the understanding it would be strictly confidential.
Mr Justice Kay also raised a question mark over whether the crimes alleged against Gen Pinochet were extradition crimes under Belgian law. Belgium is one of four countries, along with France, Switzerland and Spain, seeking the general's extradition in relation to the disappearance of relatives of Chileans now living in Belgium.