LONDON (AP) — 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 resources from April 2010 to May 2015.

Giving evidence at Southwark Crown Court in London, Alison-Madueke said “I did not abuse my office during that period.” She denies five counts of accepting bribes and a charge of conspiracy to commit bribery.

Olatimbo Ayinde, 54, an owner of Nigerian oil companies, denies two charges of bribery. Alison-Madueke’s brother, former archbishop Doye Agama, 69, denies conspiracy to commit bribery.

“I can state categorically at no time did I ask for, take or seek a bribe or bribes of any sort from any of these persons,” Alison-Madueke said.

The former minister had oversight of the state-owned Nigerian National Petroleum Corp. and its subsidiaries, the Nigerian Petroleum Development Co. and the Pipelines Product Marketing Co.

Alison-Madueke told the court that the logistics and financial dealings of her work trips were handled by the Nigerian National Petroleum Co., and insisted that a string of services arranged for her were subsequently reimbursed.

Alison-Madueke was the first female president of the oil alliance OPEC. As a minister, she had pledged to transform the oil sector but was accused by authorities of looting millions of dollars in public funds alongside her associates.

Nigeria’s anti–graft agency previously secured court orders seizing houses, cars and jewelry in Nigeria said to be proceeds of corruption connected to the former minister and her associates.

Authorities say that many such assets were domiciled in the United States and the United Kingdom.

She has spent much of her time in the U.K. since leaving office.