The U.K. Financial Conduct Authority fined Barclays, one of the world's most prominent banks, a record amount of $109 million on Thursday, alleging that the bank agreed to a series of shady financial deals with extremely rich clients, according to CNN Money.

The FCA stated that the U.K. bank, which has a market capitalization of about $56.7 billion, agreed to go into "unacceptable lengths to accommodate the clients." The clients were allegedly members of the ultra-rich and were "politically exposed persons."

Mark Steward, director of enforcement and market oversight at the FCA, said that by agreeing to keep the deal under wraps, the bank had practically agreed to overlook a number of its own pertinent processes, reports CNBC News.

"Barclays ignored its own process designed to safeguard against the risk of financial crime and overlooked obvious red flags to win new business and generate significant revenue. This is wholly unacceptable," he said.

Known as an "elephant deal," the transaction allegedly took place from 2011-2012, and was worth billions of dollars. By agreeing to the deal, the bank supposedly earned a commission of about $78 million.

The FCA has even further alleged that due to the extremely secretive nature of the deal, the bank went to such great lengths as purchasing a safe to keep the clients' documents secure. For its part, however, Barclays has stated that despite the allegations, there has been no evidence that a crime has been committed.

The bank further stated that it "continues to apply significant resources and training to ensure compliance with all legal and regulatory requirements."

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