Insights from the UK and beyond
from Royal Wedding Diary:
Will Prince William and Kate Middleton's big day be overshadowed by a minority of protesters smashing up central London and attacking police?
That's the fear of ministers and senior officers after a few hundred anarchists broke off from a mass march by unions through central London at the weekend and smashed the front of shops, banks, and the exclusive Ritz hotel among others.
Instead of pictures of the happy couple waving to crowds as they ride in a carriage from Westminster Abbey to Buckingham Palace, the worry is hundreds of millions of global TV viewers will instead be treated to images of black-clad protesters scuffling with officers.
It wouldn't be the first time that those angry with the government's public spending cuts and tax rises have taken out their anger on the royal family.