The son of Russia’s Deputy Prime Minister joined in a vodka-fuelled brawl that left a City banker needing 25 stitches to his face, a court was told.

Petr Zhukov, 24, the son of Aleksandr Zhukov, repeatedly punched Ben Ramsey in the head and body after he tried to gatecrash a Russian party, it is claimed.

Police found Mr Ramsey, 25, on the pavement outside a London block of flats covered in blood from head to toe, said Richard Milne, QC, for the prosecution.

He was taken to hospital and required five stitches to his cheek and twenty to his lower lip. A crushed cheekbone, cuts on the back of his head, two cracked ribs, a swollen jaw, and bruises to his arms, shoulder, chest and legs were among his injuries.

A trail of blood led to the door of a flat in Albany Court, Whitechapel, East London, and Mr Zhukov, who is also an investment banker, was found in a bloodstained shirt.

Mr Ramsey, who is a banker for a Japanese investment firm, lived in a neighbouring flat and he and his friend Barry Whyte tried to join the party after hearing loud dance music.

A fight broke out when Mr Zhukov’s friend Artjom Dahko, 27, who owned the flat, tried to persuade them to hand over their beers and leave, it was alleged.

Mr Milne told Southwark Crown Court: “Mr Dahko, without any warning whatsoever, punched Mr Ramsey on the forehead. Mr Ramsey started to bleed and Dahko continued to punch him.

“Mr Zhukov intervened as a peacekeeper and made an attempt to restrain Mr Dahko. That was short-lived, as Mr Zhukov then started to hit Mr Ramsey. They continued to attack him even when he stumbled to the ground.”

Dennis Virin, 23, who had been with Mr Zhukov and Dahko at the time, also jumped on Mr Ramsey’s back during the attack, the court heard. He has not been charged.

Mr Ramsey lost consciousness before staggering to his feet and fleeing the building.

His friend called police and the three men were arrested after the incident last July.

When police arrested Dahko and Mr Zhukov they were drunk and had cuts on their knuckles, but the Deputy Prime Minister’s son claimed that he was acting in self-defence.

He told police a fight broke out between Dahko and Mr Ramsey and he tried to break them up, then lost his temper and punched Mr Ramsey when he became abusive.

Dahko, Mr Zhukov and Mr Virin, had been drinking lager and vodka since 7.30pm and talking and listening to traditional Russian music, the court heard.

Mr Zhukov, who lives in West Hampstead, denies unlawful wounding Mr Ramsey and an alternative charge of assault causing actual bodily harm.

Dahko, of Islington, awaits sentence after admitting unlawful wounding.

Mr Ramsey, 26, told jurors he thought he was being attacked by “serious criminals — drug dealers or gun smugglers”. He said he had downed five pints of beer and half a bottle of wine in the West End in the hours before the attack.

The trial continues.

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