Topshop boss Sir Philip Green has been fined £1,500 over a stunt to promote TV show Stranger Things in the retail chain’s Oxford Street store.

Advertisements for the Netflix science fiction programme went up despite warnings from the council that they would be in breach of the law, Westminster Magistrates’ Court heard.

The adverts formed part of a promotion to mark the second series of the drama series, which is set in the 1980s, in the days leading up to Halloween last year.

Topshop financials
A guilty plea to a planning breaching charge was entered on behalf of Sir Philip and his company (Isabel Infantes/PA) (Tim Goode/PA)

Neither Sir Philip, 66, nor a representative from the firm, comprising Topshop and Topman, appeared in court on Wednesday.

Barrister Ian Winter entered a guilty plea to a single charge of breaching planning rules on behalf of both the businessman and his company.

Magistrates fined Sir Philip and his company £1,500 each and ordered them to pay a combined £2,908 in costs.

Prosecutor Kirsty Panton said the adverts, including a black silhouette depicting trees and roots, went up on the shopfront last October after a Westminster City Council officer explained to both Sir Philip and the estate manager of the Arcadia Group, which owns Topshop, they would be unauthorised.

“It is the prosecution case that Mr Philip Green was aware of the situation,” she said.

“He was aware the advertisements going up without consent would be an offence.”

Mr Winter said the adverts were put up to entice people into Topshop to buy items, including baseball caps, relating to the TV show Stranger Things.

“I am here expressing a sincere apology. This is something that should never happen,” he said.

The barrister explained it was a result of a “significant failure” in the company’s arrangement with a subcontractor, who had “completely overlooked the necessity of contacting the council”.

He said Sir Philip was wrongly advised by company lawyers that if there was no lettering on the hoarding it would not qualify as an advert.

“These rules are in place for a good reason. We breached them and we are extremely sorry,” he added.

“It will not be happening again.”

A Westminster City Council spokesman said: “We love bringing exciting displays to our streets and welcome new ideas from businesses.

“However, during this dispute, Mr Green personally attempted to browbeat our staff into allowing the installation of advertising hoardings on a listed building.

“When we refused, he ignored us and had the hoardings installed anyway. We had no choice but to prosecute and are pleased the case has been resolved.”