Nigeria's corruption watchdog, the Economic and Financial Crimes Commission (EFCC), has filed multiple corruption charges against former Attorney General Mohammed Adoke, who is suspected of taking bribes to facilitate a $1.3bn (£845m) oil block sale.
Multinational oil giants Shell and Eni's local subsidiaries were also charged with illegally assisting Mr Adoke.
Mr Adoke has denied any wrongdoing. Shell and Eni have also denied any wrongdoing.
The sale of an offshore oilfield known as OPL 245 by Malabu Oil and Gas in 2011 triggered an international investigation that included Shell and Eni along with a number of former Nigerian politicians.
Mr Adoke served as attorney general from 2010 to 2015.
Interpol arrested him in Dubai in November 2019. He was then detained by the EFCC.