Tycoon in marathon effort to help charity

Yesterday, the businessman said he intended to complete the gruelling 26-mile course, but admitted that he had no idea how long he would take to do it.

Mr Melville said: "It's going to be a real challenge to raise that sort of money, but it's for such a worthy cause.

"Twenty-six miles is a very long way – it's half-way from Aberdeen to Dundee.

"The training will be tough, but I am very committed. I started training two weeks ago. This week I'm building up to run 26 miles – so at least I'll know I will be able to complete it in one week!"

The chairman Cosalt Offshore, who is listed to be worth over 100 million, said he would not be taking training advice from the promotion-chasing Dundee footballers.

He joked: "They had best concentrate on the matter in hand, rather than giving me tips."

Mr Melville and his wife Susan have three children, Scott, 16, Sophie, 13, and Louise, 6.

Their efforts to help less fortunate children were inspired by their youngest daughter, whom they adopted from an orphanage in China.

Mr Melville said he had been looking for a worthy cause to start fundraising for when he came across the hospice charity.

And he hopes his efforts will also help to raise the profile of the Chas organisation, which provides help and support for families and young people suffering life-limiting conditions.

Runners from more than 100 countries will set out on 10 October from Chicago's Grant Park to raise cash for charities.

Mr Melville added: "Chas provides much-needed support for children and young people from all over the country who are facing a far shorter future than anyone deserves, with courage and dignity."