UK Home Secretary Jack Straw has said there would be "no purpose served" in continuing extradition proceedings against former Chilean dictator General Augusto Pinochet.

In a statement to the House of Commons, Mr Straw said four independent clinicians reached the "unequivocal and unanimous conclusion" that General Pinochet's condition had deteriorated significantly and he was unfit to stand trial.

He said it was unlikely his condition would improve and he said that, subject to further representations, he was "minded to take the view that there is no purpose served in considering the current extradition proceedings".

Shadow home secretary Ann Widdecombe immediately attacked Mr Straw's handling of the Pinochet case and said it had been "bungling and incompetent".

Mr Straw said he had written letters to the Crown Prosecution Service, the Spanish Government and several human rights groups informing them of his decision.

He said he had already written to the French, Belgian and Swiss Governments - who also have pending extradition warrants for General Pinochet - and given all interested parties seven days to submit their representations.

But the home secretary said he would not be making public the medical report as General Pinochet was entitled to doctor-patient confidentiality.

Mr Straw said while the case remained sub judice his comments would have to be "heavily circumscribed" but he promised to make a full statement when the legal proceedings were over.

Miss Widdecombe said there had been an "enormous expenditure of public money and of time and of effort" on the case and she demanded to know why he had not ordered such a medical report months earlier.

She also criticised the fact that Mr Straw's decision had apparently been leaked to the media before Parliament was informed.

The home secretary's decision has already been welcomed by the Chilean Government and the 84-year-old general's supporters.

But human rights campaigners and relatives of those who disappeared during General Pinochet's regime have questioned Mr Straw's handling of the case.

'Make medical report public'

Carlos Reyes, a spokesman for Chileans living in exile, said: "We are going to challenge Mr Straw's decision through every means possible and we are going to challenge the decision to keep the medical report secret.

"This report must be made public so we can be clear upon what grounds the decision has been made."

Meanwhile, Chile's ambassador to London, Pablo Cabrera, said if the general was sent home, he was likely to be stripped of his immunity and taken before the courts.

Mr Cabrera added: "It is time for Chileans to resolve their own problems, particularly as democracy is strengthening in Chile."

But Ann Clwyd, Labour MP for Cynon Valley and chairwoman of the Parliamentary Human Rights Group, said she doubted he would ever be brought to trial in Chile.

She called on Mr Straw to release the medical reports and insisted it would not be a breach of doctor-patient confidentiality.

"According to advice which I have obtained, legal precedent clearly allows for the release of such medical information, providing that it is in the public interest to do so," she said.

Mrs Clwyd said it should be up to the Spanish courts to decide if General Pinochet was fit for trial and added: "After all, nobody is suggesting that Pinochet isn't fit enough to travel the long journey home to Chile."

General Pinochet could still face prosecution in the UK, mounted either by the Director of Public Prosecutions or a through a private action brought by campaigners.