In an unusually frank admission about the mechanics of business in oil-rich West Africa, a top Equatorial ­Guinean official has said that companies owned by ministers often bid for ­government contracts with foreign groups and, if successful, receive “a percentage of the total contract the company gets”.

Teodorin Nguema Obiang, the 37-year-old son and likely successor of President Teodoro Obiang Nguema Mbasogo, made the statement in a sworn affidavit to Cape Town’s High Court, where his lawyers will today oppose the seizure of two luxury houses he owns in the city. Equatorial Guinea is sub-Saharan Africa’s third-largest oil producer.