A change to the cone on the head of a statue of the Duke of Wellington in Glasgow – an iconic image of the city – was not made by famed street artist Banksy, the PA news agency understands.

The artist’s popular Cut And Run exhibition opened at the city’s Gallery of Modern Art in June and closed on Monday.

Just feet from the entrance to the gallery, the statue of the 19th century politician and military commander riding a horse has for years had an orange traffic cone adorning its head.

The image has become synonymous with Glasgow, and Banksy has described it as his favourite artwork and part of the reason he decided to hold his first exhibition in the city.

Following the end of the exhibition, photos taken by PA show a new cone in place on the statue, this time with a propeller on top and a black stripe at the base, while a regular traffic cone appears to have been placed under the arm of the duke.

But it is understood the change was not made by the artist, leaving the identity of the perpetrator unknown.