New Delhi, April 14 -- A former Nigerian oil minister accused of staying in luxury homes for free and enjoying lavish spending sprees in exchange for government contracts denied taking bribes as she gave evidence in a London court on Monday.

Diezani Alison-Madueke, 65, is accused of benefiting from access to multimillion-pound U.K. homes that were paid for and refurnished by energy firms seeking government contracts in Nigeria.

Prosecutors allege that she benefited from private jets, a chauffeur-driven car and shopping trips including 2 million pounds ($2.7 million) spent at Harrods, a famed London department store. They also allege that she received 100,000 pounds ($135,000) in cash while she was Nigerian minister of petroleum resource...