Germany's reputation for organisation was tested on Wednesday as anti-globalisation protests tipped the G8 summit into logistical chaos and world leaders bickered over issues both on and off the meeting's agenda.

The day started poorly for Angela Merkel, the German chancellor and host of the summit, when thousands of protesters defied a ban on their approaching the fence surrounding the summit's venue - inflicting an embarrassing defeat on the formidable and expensive security apparatus.