A guilty plea would avoid a trial that is scheduled to begin next month. Hundreds of potential jurors had already been summoned.
Calls seeking comment to Santos, his attorney and federal prosecutors with the Eastern District of New York were not returned.
Santos, who was expelled from the House of Representatives, faces 23 felony charges that accuse him of defrauding donors, lying about his finances and needlessly accepting unemployment benefits among other things.
It was not immediately clear to which charges Santos is expected to plea or what sentence would be imposed.
Santos allegedly misrepresented elements of his background and biography during his campaign to represent parts of Queen's and Nassau County but the criminal charges to which he has pleaded not guilty mainly involve money.
Two associates, including Santos' former campaign treasurer, have pleaded guilty to charges over their role in his alleged fraud.
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