Developed countries must do more to help developing countries combat corruption, a United Nations conference in Bali studying graft was told on Monday.

Ngozi Okonjo-Iweala, a managing director of the World Bank, told delegates that international institutions and the private sector must also contribute because they hold most of the $20bn-$40bn (€13.5bn-€27bn, £10bn-£20bn) in developing country state assets stolen each year.