The person scaled the 30-foot statue of Prince George, the Duke of Cambridge, at around midday today (November 23), staying up there until nearly 3pm.
The stunt gathered a huge crowd and heavily disrupted traffic as police officers on the scene were forced to close off a 100-metre stretch of Whitehall.
At one point, the man stood and balanced himself on top of the statue's head.
The unidentified person - believed to be in his 30s or 40s - eventually climbed down. He was then put into a police van.
Scotland Yard have stated that he is currently being detained under the Mental Health Act.
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