Chelsea FC owner Roman Abramovich secretly married his third wife up to seven years ago

The Russian billionaire, 48, who is estimated to be worth £6.3billion, met 33-year-old art collector Dasha Zhukova in 2005 - and she has always been referred to as his girlfriend.

But now, the Moscow-born editor-in-chief of art and fashion magazine Garage has confirmed in a magazine interview that they married 'a few years' after meeting, in a secret ceremony.

The Wall Street Journal Magazine article by journalist Tony Perrottet made a reference to the couple who ‘met in 2005 and were married a few years later; they have two children’.

The simple mention in the middle of the article is understood to have been approved by Miss Zhukova, but she was unwilling to say anything about their marriage, reported the Daily Mirror.

Miss Zhukova - who met Mr Abramovich at a New Year's Eve party hosted by her father - grew up in California.

Her father is a prominent businessman and oil magnate and her mother was a scientist. Her parents split when she was three and she and her mother moved to the US when she was ten.

She went to a privileged Jewish day school in California and graduated from the University of California, Santa Barbara before returning to Moscow and later moving to London.

She and Mr Abramovich have two children - Aaron Alexander, born in December 2009 and Leah Lou, born in April 2013. Mr Abramovich has five other children from a previous relationship.

Marat Safin and Dasha Zhukova

Miss Zhukova was previously with Marat Safin, the retired former Tennis World Champion Number 1, but the couple split in 2005. Mr Abramovich meanwhile has been married twice previously.

His first wife was Olga Yurevna Lysova, whom he divorced three years after marrying in 1988. His second wife was air stewardess Irina Vyacheslavovna Malandina - with whom he had five children.

Abramovich and Irina

She married Mr Abramovich in 1991 but they divorced 16 years later in 2007 - in a settlement said to be in the region of £150million. It is thought Irina was left with a lump sum as well as four homes.

London-based Mr Abramovich is now said to own dozens of properties including nine flats in Kensington, which he plans to turn into a 30,000 sq ft house, as well as a mansion in Kensington Palace Gardens - which he reportedly bought for £90million - and a home in Chelsea.

He also owns two houses in the Caribbean, a ranch in Colorado, a house just outside Moscow, and the £250million New Holland island off St Petersburg.

He also owns two planes – a Boeing 767 and 737 – three helicopters, a customised Ferrari, two Maybach limousines, a Porsche Carrera, a Rolls-Royce Corniche and a VW Golf, as well as at least three supersize yachts.

Miss Zhukova hit the headlines in January 2014 when she apologised after being accused of racism by posing in a chair that resembled a bound and semi-naked black woman.

The photograph that showed her sitting in the chair designed by Norwegian artist Bjarne Melgaard was published 'completely out of context', she said at the time, adding: 'I utterly abhor racism.’