Yahya Ibrahim, who has described Jews as "monkeys and pigs" and is accused of advocating conflict with the West, is due to speak at the University of Wales Institute, Cardiff (UWIC), next month and at Birmingham University in March.
He is one of at least five extreme Islamists who have been allowed to enter the UK in recent years despite being banned by countries such as the United States or Australia.
WHY IS HE BEING ALLOWED TO ENTER THE U.K.?