The County Mayo island owned by Irish-Egyptian entrepreneur Nadim Sadek, who featured in the 'Secret Millionaire' series, has been sold for more than $3.81 million by receivers.

According to the Irish Independent, Sadek is reported to have spent $12 million transforming the private island of Inish Turk Beg into a world-class luxury destination.

Sadek reportedly bought it for about $1.3 million in 2003 when he outbid Irish boy band singer Ronan Keating.

Sadek fought to retain control of the island but within months the property was reportedly placed under the control of joint receivers Andrew O'Leary and Kieran Wallace of Irish professional services company KPMG, who then appointed Knight Frank Ireland and Sherry FitzGerald as joint agents.

Robert Ganly of KFI, who negotiated the sale, told the Irish Independent it took just over four months to sell, following huge interest from international purchasers.

An as yet unnamed UK resident has reportedly bought the 65-acre island with its six-bedroom house complete with large indoor swimming pool with views of the Croagh Patrick mountain, as well as five luxurious island houses.

Its facilities also include a floating jetty, a sports complex, facilities for a home cinema, a gym, an Irish dance hall and an outdoor sound system.

The new buyer will reportedly move to the island as a permanent resident later this year.

Meanwhile Nadim and his wife Sandra Sadek moved back to London last summer where he has been managing the career of his singer-songwriter daughter, Shaefri.

The Irish-Egyptian businessman made his fortune from market research and the sale of his firm Sadek Wynberg in 2003.