At the moment, all tubes and services are running pretty much as normal and the rioting has not been at the main tourist sites, but I would watch the news very carefully before making a decision.
If the rioting continues, you may wish to try and change your journey perhaps? almost 8 years ago
I suspect it'll be all over by next week. Even if it's not it'll depend on where you go. We have a link to a live incident map on the "London travel alert" on the front page of world nomads safety: safety.world nomads.com, check it out. almost 8 years ago