The Justice Department is finalizing a settlement set to be announced Wednesday morning with five major international banks that stand accused of rigging the currency market, according to multiple people familiar with the matter.

JPMorgan Chase, Citigroup, Barclays, the Royal Bank of Scotland, and UBS have reportedly spent recent weeks preparing for guilty pleas to U.S. government accusations that they engaged in criminal antitrust and fraud violations, including manipulating foreign-exchange markets. Prominently at issue: whether traders the banks employed attempted to manipulate benchmark currency prices through instant-message communications with rivals at other companies.

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On Wednesday, said the people familiar with the matter, the holding companies of at least some of those banks are expected to make the reported guilty pleas, and the group of banks expects to pay combined fees of multiple billions of dollars to settle the matter. An exact figure could not yet be determined.

Spokespeople for JPMorgan, Citigroup, Barclays, and UBS declined to discuss the details of the guilty pleas or the exact fines. A spokesman for RBS did not respond to a request for comment.

The Justice Department investigation, which parallels a similar undertaking launched by Britain's Financial Conduct Authority in 2013, has been long anticipated.