Actor George Clooney has accused South Sudan's political and military elite of being involved in "massive criminal behaviour".

Mr Clooney's investigative unit, The Sentry, commissioned a report that accuses President Salva Kiir, opposition leader Riek Machar, and top generals of profiteering.

The actor and campaigner warned international banks that those who wished to continue doing business with South Sudan would be "named and shamed".