The organisation is calling for their immediate and unconditional release, believing that they have been convicted solely for their peacefully held views.

Twelve of the defendants - including the three British men Maajid Nawaz, Ian Malcolm Nisbett, Reza Pankhurst - received sentences of five years' imprisonment.

Amnesty International UK Media Director Lesley Warner said:

'Today's news that the men have been convicted after unfair trials is disturbing in the extreme and a grievous blow to their families.

'The men have been detained for over a year and a half and dragged through a special court that denies the right of appeal. We believe that they have been convicted solely for their peacefully held views. They are prisoners of conscience who should be released immediately.

'Most worryingly of all, reports that the men were tortured during the initial period of detention last year, when they were held incommunicado - without access to the outside world - have never been investigated. Thorough, impartial and independent investigations must be opened into these allegations. Those responsible must be brought to justice.'

The three British men and a number of the Egyptians were held for weeks in incommunicado detention at premises of the State Security Intelligence, after their arrest in Cairo in April and May 2002. Amnesty International is renewing its call for long-standing torture allegations to be investigated.

The organisation has received information that several of them were subjected to electric shocks and other forms of torture and ill-treatment. Along with a fourth Briton - Hassan Rizfi - who was later released, the British men allege that they were tortured at the headquarters of the State Security Intelligence (SSI) in Cairo, where torture is systematically practised.

During their detention the three British men wrote direct appeals from their prison cells to Prime Minister Tony Blair repeating their allegations that torture was used to force 'confessions' from them. They urged Mr Blair to intervene on their behalf. Their case was reportedly raised with the Egyptian authorities by Foreign Secretary Jack Straw during a visit to the country.

The trial of the 26 men was heard by the (Emergency) Supreme State Security Court in Cairo, an exceptional court that violates international fair trial standards. This court denies defendants the right to appeal against a verdict.