Art restorer Amy Griffin, from the Simon Gillespie Conservation Studio, says that it should be possible to remove the graffiti without damaging the original painting.
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Camden Council is evacuating five tower in the Chalcots estate in north London, to allow "urgent fire safety works" to take place.
Scotland Yard said it was taking action under public order laws over the marches "due to concerns of serious public disorder".
The Football Association says it is hoped that the match will raise around £1.25million for the victims.