Police have separated a small group of anti-Muslim protesters from a crowd outside a northwest London mosque.

Police prevented members of Stop Islamification of Europe from approaching a crowd of several hundred that had gathered outside the Harrow Central Mosque.

Police stepped in as a group of about 20 men approached the crowd, which had gathered to show support for the area's Muslims.

Anindya Bhattacharyya, spokesman for United Against Fascism, says the anti-Islam protest would have set a dangerous precedent.

"A line has been drawn in the sand today," he said. "These far-right groups have organized protests outside mosques in Denmark and other countries. This is the first time they've tried it in Britain and I'm relieved it failed."