A man who swam around the island’s coastline for charity has warned the island ’could be at risk of being implicated in corruption and money laundering cases’.

Michael Davis, from London, swam around the island to raise money for two wildlife charities and updated people using his blog, which towards the end of his challenge he used to criticise the Isle of Man’s financial services.

Mr Davis is the director of campaigns, planning and evaluation at Global Witness, an international NGO that works to ’break the links between natural resource exploitation, conflict, poverty, corruption, and human rights abuses worldwide’.

In his penultimate blog, Mr Davis talked about a Manx registered business allegedly involved in corruption that related to an oil deal in Liberia.

He said: ’But is this just a case of one particularly bad apple? Unfortunately, the answer may well be no. There are, in fact, a range of other indications that the Isle of Man could be at risk of being implicated in corruption and money laundering cases.’

Mr Davis also wrote about Isabel dos Santos, an Angolan woman who bought a £13m house in Kensington using a Manx company, which we reported last month.

He said: ’There are 10,704 unique freeholds and leaseholds owned by at least one Isle of Man firm. Over a third of the Isle of Man company-owned properties in England and Wales are in Greater London, with the highest concentrations in the City of Westminster and Chelsea and Kensington, where Isabel dos Santos has her mansion.

’Who are the owners of all this property? The answer is that we don’t know because the Isle of Man does not yet allow public access to its register of company beneficial owners.’

Mr Davis said that Manx companies are being ’used as a vehicle by people like Isabel dos Santos’. He added: ’Why would they go to the trouble? Perhaps to avoid paying taxes. Maybe because they don’t want people to know who they are and the source of their money.’