The University of London has cancelled the appearance of a speaker from an Islamic group that opposes democracy and integration into British society.
A representative of Hizb ut-Tahrir was due to appear at Queen Mary college in east London to debate Sharia law in the modern world.
But the group was told it could not take part after students campaigned about its "blatantly aggressive" views.
The university's union said the debate organisers acted to avoid controversy.
Hizb ut-Tahrir has previously said "those who believe in democracy are Kafir" [unclean] and said it was "dangerous" for Muslims to integrate into British society.