Britain has unveiled the criteria it will use to bar foreigners it believes inspire terrorism as part of a broad crackdown on Islamist preachers after last month's bombings in London.
Interior Minister Charles Clarke published a list of "unacceptable behaviors" which would prompt deportation or a ban on entry.
"The terrorist threat facing the UK remains real and significant and it is right that the Government and law enforcement agencies do everything possible to counter it," said Mr Clarke in a statement.
"That includes tackling those who seek to foster hatred or promote terrorism, sending a strong message that they are not welcome in the UK."
The list of activities, which covers any non-UK citizen in Britain or abroad, includes expressing views which foment, justify or glorify terrorist violence in pursuit of particular beliefs and seeking to provoke others to terrorist acts, ABC.
According to Forbes, the list was shorter than a draft proposed by Clarke three weeks ago, but the Home Office said the final version was 'indicative rather than exhaustive'.
The banned views could be aired by writing, producing or distributing material, public speaking or over an Internet site.
They could also be delivered by someone in a position of responsibility such as a teacher or a community leader.
Clarke said a database of people worldwide who Britain believed had behaved unacceptably would be developed and made available to immigration officers.
Dismissing fears of an infringement on free speech, the minister said: 'These powers are not intended to stifle free speech or legitimate debate about religions or other issues.'
Inayat Bunglawala, a spokesman for the Muslim Council of Britain, disagreed, arguing the criteria were too vague.
'These rules have the very real potential of harming those engaged in legitimate struggles against oppression and human rights abuses,' he said.