Braving a temperature of 6 degrees Celsius, the man climbed the statue of Prince George in Whitehall, London, took off his clothes and proceeded to pose naked, waving at onlookers.
The incident, which happened at midday, brought London's traffic to a standstill for around three hours, as police feared the man might pose a security risk.
Described as an inconspicuous man in his thirties or forties, he clambered up the bronze statue of Prince George, the Victorian-era commander-in-chief of the British Army, which is outside Whitehall, and houses the UK government and Ministry of Defence.
Striking various provocative poses, he even climbed on top of the feathered bicorne worn by the general, and attracted crowds of onlookers, taking photos with their mobile phones.
The incident attracted a response team of four police cars, two fire trucks, and four mounted policemen, who blocked off the area within 100 meters of the statue. This forced government employees to enter their buildings through alternative routes.
Eventually, after three hours, professional negotiators managed to urge the man to climb down. He was then detained under the Mental Health Act.
More images of the streaker can be viewed on RT.