Kofi Annan's son apparently made a million pound profit by purchasing a luxury flat on the King's Road, Chelsea, using an offshore company named in the Panama Papers.

According to leaked Mossack Fonseca documents, Kojo Annan, 42, the former United Nations Secretary General's only son, used the Samoan company Sapphire Holding Ltd to buy the property in 2004 for £400,000. Market data show that it is now worth up to £1,559,293.

This is the latest in a string of allegations about Mr Annan, including that he took advantage of his powerful father to win business contracts, and avoided tax while shipping a green Mercedes 4X4 to Ghana.

He has denied any wrongdoing.

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Wealthy: Kojo Annan, who has been linked to a number of controversial businesses, seen here with his wife Shanthi

Holiday: Shanthi Annan has posted a photograph of herself enjoying an exotic holiday in Mykonos, one of the most popular and glamorous Greek islands, on Facebook

All smiles: Shanthi and Kojo Annan appear relaxed as they are driven around in Britain, where they live

Hobnobbing: Kojo Annan, left, and his wife Shanthi Annan, right, pictured with Tory donor Alisa Swidler, centre

Mossack Fonseca was communicating with Annan at his Chelsea address as recently as 2015.

Mr Annan and his wife, Shanthi, 30, are now directors of a London-based company called A10 Enterprises, described as offering 'business support service activities'. They have also been linked to prime property in New York and Accra, Ghana.

Kojo Annan, who is known for his charming personality, faced an investigation after his employer, Cotecna, won a multi-million-pound UN contract to act as a watchdog in the 'oil for food' programme while his father was in charge.

'OIL FOR FOOD' CORRUPTION The £45billion UN 'oil for food' programme ran between 1995 and 2003. It allowed Saddam Hussein to sell oil for humanitarian aid but not arms, and was notorious for corruption. An independent commission found that the UN official in charge, Benon Sevan, 'corruptly benefited' from kickbacks while he was in charge. An 18-month inquiry found widespread malpractice among UN officials and revealed Saddam stole £1billion, triggering calls for Kofi Annan to resign. He managed to stay in his job. Advertisement

A 2005 inquiry officially found 'no evidence' that the decision to award the contract to Cotecna 'was subject to any affirmative or improper influence of the Secretary General', but faulted Kofi Annnan for inadequately investigating the affair.

It said that Kojo Annan may have earned as much as £344,000 in consulting fees from Cotecna while it did business in Iraq for the UN.

In a press conference now available on YouTube, Paul Volcker, head of Independent Inquiry Committee, told reporters that although no evidence of malpractice was found, Kojo Annan had 'disguised' the nature of his involvement in the deal.

'Both Cotecna officials and Kojo Annan acted to disguise their continuing business and financial relationship, misleading the Secretary General himself, other UN officials, and the public,' he said.

'It is the failure of UN officials to discover, and of Cotecna and Kojo Annan to fully disclose, these relationships that has contributed so heavily to the questions about the integrity of the UN administration and the need for this particular report.'

In a statement, Kofi Annan said he had been 'exonerated'. However, Mark Pieth, a senior member of Volcker's team, told reporters that this was an exaggeration.

'We did not exonerate Kofi Annan,' he said. 'We should not brush this off. A certain mea culpa would have been appropriate.'

A US State Department official also disputed Annan's use of the word 'exoneration', and the FT reported that two senior members of the investigating body resigned because they felt the report 'played down critical findings'.

Kojo Annan later claimed to own a top Nigerian football team in order to be elected president of Vevey-Sports, a small Swiss football club, according to the New York Post.

Shortly afterwards, a Cotecna executive made a payment of £8,000 to Mr Annan through the football club. Cotecna insisted the payment was not linked to the UN contract scandal.

Mr Annan was rarely seen at the club, instead leaving its management to a local businessman, Roland Frey, who was later jailed for embezzling £35,000 and other financial improprieties.

According to the FT, Paul Gabarni, who coached the team, said: 'I never quite understood what had got [Annan] interested in a club like Vevey. The truth is that in Swiss football, if someone brings the money, nobody really asks why.'

Kojo Annan again hit the headlines in 2006, when he bought a green Mercedes 4X4 using a £4,600 diplomatic discount by claiming that his father was the owner. He then shipped the car to Ghana, avoiding a further £7,900 in customs duties, by apparently using his father's name.

As recently as 2012, Kofi Annan appeared to be using his position to support his son's endeavours when he featured in a promotional video for a film that Kojo Annan produced without declaring his interest.

Kojo Annan, Cotecna and Kofi Annan have consistently denied any malpractice.

Dodgy: Kojo Annan falsely used his father's name to purchase a green Mercedes 4X4, allowing him to claim a diplomatic discount and avoid customs duty when he shipped it to Ghana

Prime property: The exterior of the Annan's £1.5m apartment on the King's Road, Chelsea, London

International: Mossack Fonseca documents have also linked Kojo Annan to an apartment in this exclusive block in New York

Luxury: Kojo Annan, centre, and two friends, enjoy a boat ride in an undisclosed exotic location

Trophy: Kojo Annan, a keen rugby enthusiast, and his wife Shanthi, pose beside the Rugby World Cup

Kojo Annan was born in Geneva in 1973 to Kofi Annan's first wife, Titi Alakija, a Nigerian now living in Fulham, London. His parents divorced shortly after he was born.

He attended Rendcomb College, a £21,000-a-year public school in Gloucestershire, where he became a talented rugby player, winning a place in the school's first team and playing for the county.

According to the Old Rendcombian Society Newsletter, only injury prevented him from 'playing against the touring Australian side and almost certainly going on to wear the red-rose jersey of England'.

Mr Annan had summer jobs at the UN in Geneva between 1992 and 1993 while reading economics and politics at Keele University .

He applied to the Swiss firm Cotecna for a job at the age of 22. 'He was looking for some training, in 1995,' André Pruniaux, a former senior vice-president of Cotecna, told a congressional hearing.

'When [my colleague] saw the background of the gentleman and [that] he was African [and] he spoke several languages, he immediately turned that to me [and] said, "Andre, are you interested?"

'I said, "Why not? Let him come to Geneva. I have always been looking for young Africans, educated, who could take over the positions of chiefs of our offices in Africa."'

Mr Annan was soon travelling the world representing Cotecna.

'Kojo was a very young man at that time,' said Robert Massey, CEO of Cotecna. 'He was trying to prove himself. He was trying to prove to me that he was, if not already yet now, soon to become efficient in trying to reach out to contacts and make his effort efficient.'

Mr Annan has said that reports on his financial affairs were 'a witch-hunt from day one as part of a broader Republican political agenda'.

In response to the Panama Papers revelations, his lawyer said that Mr Annan's companies 'operate in accordance with the laws and regulations of the relevant jurisdictions and, insofar tax liabilities arise, they pay taxes in the jurisdictions in which taxes are due to be paid.'

He added: 'In other words, any entity and account held by Mr. Annan has been opened solely for normal, legal purposes of managing family and business matters and has been fully disclosed in accordance with applicable laws.'

The lawyer also highlighted the fact that the 2005 investigation found no evidence that Mr Annan had tried to influence anyone in the UN to award contracts to any company with which he was associated.

Charming: Mr Annan, who has a taste for luxury, has earned a reputation as an extrovert and a playboy