James Onanefe Ibori, one of Nigeria's wealthiest politicians, has been charged in London with 25 offences relating to money laundering and fraud.
Mr Obori was governor of oil-rich Delta state between 1999 and 2007 and has been under investigation in the UK for some years, for allegedly stealing $290 million in state assets and depositing them in UK bank accounts.
State governors, and especially those in oil-rich regions, enjoy extensive powers. While in office Mr Obori had immunity from prosecution He was arrested in Dubai in May 2010 and then extradited to the UK to face the charges.
The UK authorities are reported to have frozen in excess of $100 million in assets that are associated with him.
Mr Obori denies allegations of corruption, stating that “there is no truth to the allegation”.