A large blue rooster currently stands on the fourth plinth at Trafalgar Square, which has become a showcase for temporary artworks.
Mayor of London Boris Johnson said: "The placing of challenging artwork amidst the historic surroundings of Trafalgar Square creates a delicious juxtaposition that gets people talking and debating, underpinning London's reputation as a great world city for culture."
More top news
Calum McSwiggan posted a photo on Instagram as he lay in a hospital bed after the alleged attack.
The London mayor publicly backed defeated candidate Owen Smith in the contest which saw Mr Corbyn re-elected party leader.
Police described it as a "growing sink hole" and it's unclear when the road will reopen.