Gordon Brown shook hands with former jihadists who were incarcerated in Guantanamo Bay and wished them well for life after release as he toured a rehabilitation centre for extremists in the Saudi Arabian capital.

The Prime Minister chatted to Juma al-Dossary, 35, and Ganim al-Harbi, 34, who were both accused of providing “logistical support to terrorist organisations”, at the secure centre on the outskirts of Riyadh.

The men, who spent six years each in Guantanamo Bay, were among the five terrorist accomplices who met Mr Brown in a government-run “halfway house” that provides reeducation, moderate religious teaching and therapy. Mr Brown was giving high-level British backing to the project, which involves 3,200 detainees in several “halfway house” centres. Downing Street emphasised that none of the individuals who met Mr Brown had been directly involved in killing people.

Last month the Interior Minister announced that nearly 1,000 suspects accused of having ties to al-Qaeda would soon be tried for carrying out dozens of “acts of war” against Saudi Arabia. There are about 6,700 terrorist suspects and convicts in Saudi jails at the moment.

Mr Brown asked the group how the programme had changed their view of society. Mr al-Dossary said that his time at Guantanamo Bay had been difficult but the reeducation programme had presented “logical” arguments for why violence was not the answer. He told Mr Brown: “I put myself in the wrong pace at the wrong time.”

Speaking after the visit, Mr Brown said: “The Saudis are committed to tackling the extremists who poison young people with their evil ideology of terror. I was glad I had the opportunity to witness how they are seeking to change the attitude of young people who would be vulnerable to falling back under the spell of extreme groups on being released.”

Opposition politicians suggested that Mr Brown must be careful when agreeing to undertake such visits. Lord Tebbit, whose wife Margaret was crippled in the 1984 Brighton hotel bombing, said: “This Government has a policy of encouraging terrorists back into normal political life, so it doesn’t surprise me to see him mingling with them in Saudi Arabia.”

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