Greek island where Aristotle Onassis married Jackie Kennedy sold for '£100m' to Russian socialite Ekaterina Rybolovleva

Kilometre-long island of Skorpios features three residences, a helipad and a boat quay

The private luxury island where John F Kennedy's widow Jackie married Greek shipping magnate Aristotle Onassis has been sold for a reported £100m by the tycoon's sole surviving heir.

Onassis's grandaughter Athina Onassis Roussel has agreed to sell the kilometre-long isle of Skorpios, which sits off the west coast of Greece in the Ionian Sea, to the daughter of Russian billionaire Dmitry Rybolovleva.

Reports of the sale emerged in Greek media earlier this week, but the identity of the buyer was not known until today.

Representatives for the Rybolovlev confirmed that 23-year-old Ekaterina Rybolovleva had bought the island as part of a group of assets belonging to Ms Onassis Roussel.

A statement issued by the family read: "A company belonging to a trust acting in the interest of Ekaterina Rybolovleva  has completed the purchase of a group of companies formerly ultimately owned by Mrs Athina Onassis.

"Amongst the assets of this group of companies are the islands of Skorpios and Sparti. Ekaterina is delighted that the trust has negotiated this purchase. She sees significant potential for further improvement of the islands using environmentally friendly technology and regards the acquisition as a long-term financial investment.”

The total figure paid for the group of companies is still not confirmed.

The forested island, which is home to three residences, a helicopter pad and a boat quay, was bought by Onassis in 1962 for 3.5 million drachmas – the equivalent of about £10,000 – and six years later he married Jackie Kennedy there, following the assassination of her former husband, US President John F Kennedy in 1963.

When he died in 1975, Skorpios was passed on to his daughter from his first marriage, Christina, and then to her daughter Athina.

Though he had not heard about the sale, a prominent broker of private islands around the world, told the Daily Telegraph earlier this week that he was not surprised that Ms Onassis Roussel had decided to sell.

Farhad Vladi, who was hired to carry out an evaluation of Skorpios eight years ago, said: "These Russian oligarchs have billions, so it may be that one of them came along and said 'I will give you 100 million or 200 million euros for it'. Anything is possible."

The Onassis family have a deep connection with Skorpios. Mr Onassis was buried there, as were his daughter Christina and his son Alexander, who died in a plane crash in 1973.

Ms Onassis Roussel, 28, who was once described as "the richest girl in the world," is Mr Onassis's only surviving descendant and heir to her grandfather's fortune. Born in France, she is the only child of Christina Onassis and her fourth husband Thierry Roussel.

She married Brazilian Olympic showjumper Alvaro de Miranda Neto in 2005 and lives with him in São Paulo. She competes as a showjumper in her own right, under the name Athina Onassis de Miranda.

Also an avid equestrian, Ms Rybolovleva made headlines last year when she bough an apartment in New York for $88m, breaking records for an individual transaction.

Her father Dmitry is one of a small group of Russians who became wealthy in the wake of post-Soviet privatisation of the economy and is the former owner of fertilizer business Uralkali.

Listed as the 79th richest person in the world by Forbes, he is the current owner of AS Monaco Football Club.