The Labour MP John McDonnell said: "We are feting this man because Saudi Arabia controls 25 per cent of the world's oil, and because we sell him billions of pounds' worth of weapons. It is an insult to everything Britain stands for to put these geopolitical concerns ahead of the rights of women, trade unionists and all Saudi people."

While King Abdullah is cheered by our political leaders, many of his victims will be protesting outside. Sandy Mitchell, 52, went to Saudi Arabia to work as an anaesthetic technician at a hospital in Riyadh more than a decade ago – and got a rare outsider's glimpse into how the king maintains his power. He explains: "One day in 2000 I was getting out of my car at the hospital when I was pounced on. I was battered to the ground, a hood was put over my head, and they manacled my hands and feet. I thought – I'm being kidnapped."

He woke up in the Madhethe interrogation centre, where the Saudi police demanded he confess to being a British spy ordered to plant bombs in the country. He told then the bombs were obviously the work of Saudi Islamists – a view now accepted to be true – so they hung him upside down and began to beat his feet and buttocks with an axe handle for eight days. All the while, he could hear his friend Bill Sampson being gang-raped in the next room.

Mr Mitchell was eventually released after 32 months, when he was swapped for several Saudi citizens being held in Guantanamo Bay. But he warns: "The torture chambers in Saudi weren't created for me. These rooms were like a human abattoir. There was years' worth of blood on the floor that nobody bothered to clean. It was all over the walls. We were lucky we survived, but there are countless Saudi people who we never hear about who don't survive those chambers." Mr Mitchell will be joined at the protests by many refugees who have narrowly escaped this fate, including the trade unionist Yahya al-Faifi.

But life in Saudi Arabia is worst of all for women. While King Abdullah offers praise for Britain's female head of state, in his country all women are kept in effect under house arrest. They are banned from driving, from leaving the house without a male guardian, even in a medical emergency, or from holding a passport. Whenever women try to struggle free from these rules, the "Commission for the Promotion of Virtue and Prevention of Vice" – a posse of uniformed thugs who stalk the streets – beat them with batons.