Of the $10 million reported Thursday, special counsel Robert Mueller's office has spent approximately $4.5 million over that period of time on salaries, rent, travel and supplies.
However, the FBI's counterintelligence investigation was in existence before Mueller's appointment.
The department explained Thursday of the $10 million amount, roughly $5.4 million was spent by other law enforcement personnel who do not report to Mueller and "would have incurred for the investigations irrespective of the existence of the [special counsel]."
Over the life of the investigation, including the last reported figures, Mueller's team has spent about $7.7 million.
But Thursday's spending report could provide fresh fodder for President Donald Trump who has taken to Twitter to slam the investigation as a waste of money.
Last weekend he tweeted, "at what point does this soon to be $20,000,000 Witch Hunt, composed of 13 Angry and Heavily