King Abdullah's Saudi regime spends billions of pounds each year promoting Wahhabism, one of fundamentalist Islam's most extreme movements. Much of it funds children's education in British faith schools and mosques. Should we be worried? Paul Vallely investigates

King Abdullah will go home to Saudi Arabia today with the charges of human rights protestors ringing irritatingly in his ears. But his controversial visit may well have left an unpleasant legacy for the people of the country which has feted him with full state honours.

There was a hint of it in a report written this week by Dr Denis MacEoin, an Islamic studies expert at Newcastle who previously taught at the University of Fez. Leading a team of researchers over a two-year project, he uncovered a hoard of malignant literature inside as many as a quarter of Britain's mosques. All of it had been published and distributed by agencies linked to the government of King Abdullah.