Individuals and organisations which look after war memorials are being encouraged to apply for free "SmartWater" kits.
A unique traceable liquid, which is painted onto the memorials, "SmartWater" is virtually impossible to remove - and can even withstand burning and sand blasting.
Today, the Duchess of Cornwall helped to protect the Royal Artillery Memorial on Hyde Park Corner, by applying the fluid with a paint brush.
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Disruption was expected to last well into the rush hour, threatening a repeat of chaotic scenes at London Bridge earlier this year.
The first written record of The Elephant and Castle pub was made in March 1765, exactly 250 years ago.
The controversial plan in east London aims to tackle anti-social behaviour linked to persistent rough sleeping and begging.