Hunter said: 'The aim is to redouble our efforts in wealth creation in order to, over time, invest£1 billion in venture philanthropy through our foundation. Great wealth brings with it great responsibility.'
Hunter pledged to donate the money to his charitable organisation, the Hunter Foundation, which he formed nine years ago after selling his sports retail business to JJB for£290 million.
Separately, an announcement is expected today on Tesco's approach for garden centre group Dobbies. It is still unclear whether Hunter will make a bid, or whether he would sell his shares to Tesco.
In the past year, a consortium led by Hunter has acquired Wyevale Garden Centres and Blooms of Bressingham.