British Prime Minister David Cameron on Wednesday unveiled a new financial institution, called the Big Society Capital, aiming to build a bigger and stronger society through financing charities and community groups.

"Big Society Capital is going to encourage charities and social enterprises to prove their business models - and then replicate them," Cameron said, adding that it would "be able to seek investment for expansion into the wider region and into the country" once proved successful.

Of the total 600-million-pound capital, 400 million pounds will come from unclaimed cash left dormant in bank accounts for over 15 years while 200 million pounds will be provided by Britain's four largest high street banks Barclays, Lloyds, HSBC and RBS.

"This is a time when we need to be doing more to back our social entrepreneurs," Ronald Cohen, Chairman of Big Society Capital, a pioneering venture capitalist and founder of Apax Partners, said in an interview with BBC.

Cohen explained that the fund's aim was to create a "thriving market for social investment" and to help out businesses that provide a benefit to society much greater than the profits they make.

Big Society Capital will be an organization run independently from the government with decisions made by an impartial investment committee.