A member of an international gang of thieves who carried out a “truly audacious” $4.5 million diamond heist at a jewellers in Mayfair has been jailed.

Mickael Jovanovic, 27, and his gang posed as Russian businessmen and invited Nicholas Wainwright, the chairman of Boodles, to meet them in Monaco and arranged a sale at the company’s store on New Bond Street.

In a raid compared by police “to the plot of a film” such as Ocean’s Eleven, starring George Clooney and Brad Pitt, the gang used distraction techniques to switch the seven diamonds, one of which was a heart-shaped jewel worth $2.7 million, with pebbles before making their getaway.

Southwark crown court was told that when the sale was arranged in Monaco the fake businessmen said their gemologist would examine the stones. On March 10, 2016, Mr Wainwright and Emma Barton, Boodles’s own gemologist, met the fake expert, “Anna”, who was taken to the basement of the shop for a viewing, where she used a sleight of hand trick.

A raid compared by police “to the plot of a film” such as Ocean’s Eleven, starring George Clooney and Brad Pitt.

Jovanovic and another man, Christophe Stankovic, who had carried out surveillance, loitered near by. Two women acted as lookouts for Anna and a third woman stood by with a change of clothes at a pub near Victoria Station.

The court was told that after Anna, who is still at large, viewed the diamonds and placed them in a small padlocked bag she had brought, a fellow member of the gang called the store.

“Anna wrapped each diamond in pre-cut tissue paper and placed them inside opaque boxes she had brought with her”, Philip Stott, for the prosecution, said. “When the examination was complete, the boxes were placed into a zipable purse-like bag. That was then padlocked shut.”

Mr Wainwright went upstairs to answer the call and Anna went to put the bag in her handbag. Ms Barton told her she could not do this but, unbeknown to the gemologist, the bag Anna placed back on the table was a duplicate containing pebbles, each in a replica box.

It was agreed that the bag would be collected after a transfer of funds. After leaving the shop, Anna met her associates in the street and handed over the diamonds, then they split up. Within three hours they were all in France.

The next day a director at Boodles spoke to the fake buyer, who confirmed that the money would be transferred. Staff grew suspicious and x-rayed the bag, discovering that they had been left with pebbles.

After the jewellers found they had been duped, the Flying Squad began an investigation and made extensive CCTV inquiries. The gang had used minicabs to try to hide their movements but their departure from the country was quickly established. Their images were circulated to other police forces.

Stankovic was caught and jailed in 2016. Jovanovic, of Le Blanc-Mesnil, a suburb in northeastern Paris, was extradited from Italy in January and arrested. He was charged the same day and admitted conspiracy to steal. On Friday he was jailed for three years and eight months by Southwark crown court. Mr Stott described the raid as “of the highest possible sophistication, planning, risk and reward”.

The jewels have not been traced and Stankovic and Jovanovic’s accomplices have not been caught.

Detective Constable William Man, of the Flying Squad, said: “This was a well-organised theft which evolved over a number of weeks. Like the plot of a film, this was a truly audacious crime. They stole the diamonds and fled in a matter of hours.

“As a result of piecing together all of the bits of information, we knew it was only a matter of time before arrests were made. And whilst it has taken four years, this case does highlight that we won’t give up. We still remain determined to identify all of those involved.”