Andrew received £15m 'from oligarch linked with bribery'

Questions around the disgraced royal’s dealings while he was trade envoy have not gone away, despite him taking a step back from public life and now living a quiet life, although there is no proof he knew of corruption in this case.

According to reports this week, Kazakh billionaire Timur Kulibayev used a loan from a company called Enviro Pacific Investments to purchase Sunninghill Park in Berkshire from Andrew in 2007.

Italian prosecutors later ruled that Enviro had received cash from a bribery scheme which involved another company called Aventall.

Now, Mr Kulibayev has told the BBC, through his laywers, that he bought the mansion with the help of Enviro just weeks after the final bribery payment came in.

It is alleged that Andrew therefore, after a chain of events, received corrupt money - although there is no evidence to say that he knew this.

The former Duke of York is set to leave his Royal Lodge this year and has been linked to starting over in Bahrain if he shirks the King’s offer of a lodging in the Sandringham estate.

Andrew lived in Sunninghill Park as his official residence from 1990 until 2004.

The Berkshire estate, where Andrew lived with his ex-wife Sarah and their daughters Princesses Beatrice and Eugenie, had 12 bedrooms, stables and a swimming pool.

It was bought by the Queen as a wedding gift for her second son in 1986 but required four years’ worth of work before the couple moved in.

Andrew moved into the Windsor mansion, the Royal Lodge, following the death of his grandmother, Elizabeth, the Queen Mother and sold Sunninghill Park in 2007.

The deal was questioned at the time as Mr Kulibayev was said to have overpaid by several million pounds, and his identity was not confirmed until it was revealed by a newspaper probe.

Andrew told the Telegraph in 2009: "It's not my business, the second the price is paid. If that is the offer, I'm not going to look a gift horse in the mouth and suggest they have overpaid me."

He was nonetheless criticised for using his trade connections to try and sell his house after it went on the market in 2001 and failed to attract any offers.

It is thought that Andrew was introduced to the Kazakh inner circle by the socialite Goga Ashkenazi, who he was friends with and was his guest, alongside the Queen, at a box at Ascot in 2007.

Ms Ashkenazi had a long-time affair with Mr Kulibayev and she had two sons with him, Adam and Alan.

Andrew visited Kazakhstan in 2006 and met its autocratic president, Nursultan Nazarbayev, who later met the Queen in Buckingham Palace.

An offer then came through from Mr Kulibayev, who is Mr Nazarbayev’s son-in-law and Andrew accepted it, although the mansion has now fallen into disrepair and plans to renovate it fell through when bats roosted within its roof, preventing the demolition.

The BBC reported a chain of events, where a company called Aventall paid bribes to Enviro, who loaned money to Mr Kulibayev, who then paid Andrew.

Therefore, the former prince may have benefited from corrupt money, according to the report, although Mr Kulibayev has not been charged with anything.

Andrew has not commented and there is no evidence that he knew of any corruption or the source of the money used to make the purchase.