Sir Richard Branson is among the latest crop of billionaires who have promised to donate at least half their fortune to charity.

The Virgin Group founder, who is worth more than $4bn, has added his name to the Giving Pledge campaign set up by U.S. investor Warren Buffett and Microsoft founder Bill Gates.

In their pledge letter, Sir Richard and his wife Joan said they wanted to use cash from the company to create ‘a healthy, equitable and peaceful world for future generations to enjoy.’

They said: ‘”Stuff” really is not what brings happiness. Family, friends, good health and the satisfaction that comes from making a positive difference are what really matters.

‘Happily our children, who will be our principal heirs, agree with me on this.

‘As and when we take monies out of the Virgin Group of companies the majority of it will be invested in entrepreneurial approaches to help make a difference in the world.’

The Giving Pledge was started three years ago by Mr Gates, his wife Melinda and Mr Buffett and within just a few months they had encouraged more than 30 other U.S. billionaires to get no board.

The initiative does not accept any money, but asks billionaires to make a moral commitment to give away their wealth to charity.

Sir Richard is among the first non-U.S. batch of signatories to join as Mr Gates and Mr Buffett decided to concentrate their early efforts on those in America first.

Others include Russian industrial magnate Vladimir Potanin and Ukrainian metals and media tycoon Victor Pinchuk.

Other prominent pledgers include Facebook founder and CEO Mark Zuckerberg, Star Wars director George Lucas and Ted Turner, the founder of the CNN news channel.